Systems and methods for handover of mobile devices, radio cells and space vehicles for mobile satellite wireless access

ABSTRACT

Access, mobility management and regulatory services are supported for satellite access to a Fifth Generation (5G) core network (5GCN). Signaling including data and voice for radio cells supported by a satellite is transported between UEs and a core network via an earth station. When the satellite is transferred to a new earth station, the signaling can be transferred to the new earth station and possibly to a new base station. The UEs may remain with their current radio cells with a regenerative satellite or be assisted to remain with their current radio cells with a transparent satellite. The signaling transfer between the earth stations may occur at a Level 1 or Level 2. A modified handover procedure may be used with a regenerative satellite with split architecture when there is a change of base station.

CLAIM OF PRIORITY UNDER 35 U.S.C. § 119

This application claims under 35 U.S.C. § 119 the benefit of andpriority to U.S. Provisional Application No. 62/932,486, filed Nov. 7,2019, and entitled “SYSTEMS AND METHODS FOR SUPPORT OF A 5G SATELLITERADIO ACCESS TECHNOLOGY,” U.S. Provisional Application No. 62/989,572,filed Mar. 13, 2020, and entitled “Methods Performed In User Equipment,Satellite Vehicles, Or Earth Stations For Enabling Third GenerationPartnership Project (3GPP) Protocol Communications, Via SatelliteRelay,” U.S. Provisional Application No. 63/010,564, filed Apr. 15,2020, and entitled “SYSTEMS AND METHODS FOR: SUPPORTING FIXED TRACKINGAREAS AND FIXED CELLS FOR MOBILE SATELLITE WIRELESS ACCESS; HANDOVER OFMOBILE DEVICES, RADIO CELLS AND SPACE VEHICLES FOR MOBILE SATELLITEWIRELESS ACCESS; SUPPORTING SATELLITE ACCESS FROM MOBILE DEVICES TOPUBLIC LAND MOBILE NETWORKS; ASSISTING RADIO CELL ACQUISITION BY AMOBILE DEVICE FOR SATELLITE WIRELESS ACCESS,” and U.S. ProvisionalApplication No. 63/028,539, filed May 21, 2020, and entitled “SYSTEMSAND METHODS FOR: SUPPORTING FIXED TRACKING AREAS AND FIXED CELLS FORMOBILE SATELLITE WIRELESS ACCESS; HANDOVER OF MOBILE DEVICES, RADIOCELLS AND SPACE VEHICLES FOR MOBILE SATELLITE WIRELESS ACCESS;SUPPORTING SATELLITE ACCESS FROM MOBILE DEVICES TO PUBLIC LAND MOBILENETWORKS; ASSISTING RADIO CELL ACQUISITION BY A MOBILE DEVICE FORSATELLITE WIRELESS ACCESS,” all of which are assigned to the assigneehereof and are incorporated herein by reference in their entireties.

BACKGROUND Field of the Disclosure

Various aspects described herein generally relate to wirelesscommunication systems, and more particularly, to accessing a wirelessnetwork using communication satellites.

Description of Related Technology

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (for example, time, frequency, and power). Examples ofsuch multiple-access systems include fourth generation (4G) systems suchas Long Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, orLTE-A Pro systems, and fifth generation (5G) systems which may bereferred to as New Radio (NR) systems. These systems may employtechnologies such as code division multiple access (CDMA), time divisionmultiple access (TDMA), frequency division multiple access (FDMA),orthogonal frequency division multiple access (OFDMA), or discreteFourier transform spread orthogonal frequency division multiplexing(DFT-S-OFDM). A wireless multiple-access communications system mayinclude a number of base stations or network access nodes, eachsimultaneously supporting communication for multiple communicationdevices, which may be otherwise known as user equipment (UE).

Standardization is ongoing to combine satellite-based communicationsystems with terrestrial wireless communications systems, such as 5G NewRadio (NR) networks. In such a system, a user equipment (UE) wouldaccess a satellite, also referred to as a space vehicle (SV), instead ofa base station, which would connect to an earth station, also referredto as a ground station or non-terrestrial (NTN) gateway, which in turnwould connect to a 5G network either directly or via a base station. A5G network could treat the satellite system as another type of RadioAccess Technology (RAT) distinct from, but also similar to, terrestrial5G NR.

Since satellites typically differ from terrestrial base stations interms of the size of their coverage areas, movement of coverage areas,longer propagation delays and different carrier frequencies, a 5Gsatellite RAT may need different implementation and support than a 5Gterrestrial RAT for providing common services to end users. It may thenbe preferable to both optimize, and to minimize the impact for, suchdifferent implementation and support.

One example of common services concerns provision of regulatoryrequirements such as emergency (EM) calls, Lawful Interception (LI) andWireless Emergency Alerting (WEA). Supporting these common servicesusing a satellite RAT should preferably have minimum new impact to aterrestrial 5G Core Network (5GCN) while still provided an equal orbetter level of service than a terrestrial 5G RAT.

Another common service concerns continuity of radio access by UEs to5GCNs and to external entities accessed via 5GCNs. Since satellites inlow and medium earth orbits have moving coverage areas, radio access byUEs may be subject to interruption. Means of mitigating or avoiding suchinterruption in an efficient manner may then be useful.

A further type of service concerns an ability to support access by UEsto 5GCNs in the same country as the UEs—e.g. in the case that asatellite coverage area spans an international border. Means to enablesame country 5GCN access may then be desirable.

SUMMARY

Access, mobility management and regulatory services are supported forsatellite access to a Fifth Generation (5G) core network (5GCN).Signaling for radio cells supported by a satellite and that istransported between UEs and a core network may be transferred betweenearth stations. Signaling is transported a plurality of User Equipments(UEs) and a core network via a space vehicle (SV) using a plurality ofradio cells, as well as an earth station and network node, such as aNodeB. The transport of the signaling between the UEs and the corenetwork may be stopped and second signaling between the UEs and the corenetwork enabled, wherein the second signaling is via the SV using theplurality of radio cells, as well as a second earth station and a secondnetwork node. The SV may operate in a transparent mode, regenerativemode, or regenerative mode with split architecture.

In one implementation, a method performed by a first network node fortransferring signaling for a first plurality of radio cells from a firstearth station to a second earth station, wherein the first plurality ofradio cells is supported by a space vehicle (SV), includes transportingfirst signaling between a first plurality of User Equipments (UEs) and aCore Network at a first time, and wherein the first signaling istransported via the SV, the first earth station and the first networknode, wherein the first signaling is transported between the SV and thefirst plurality of UEs using the first plurality of radio cells; ceasingto transport the first signaling between the first plurality of UEs andthe Core Network at a second time, wherein the second time is subsequentto the first time; and enabling the transport of second signalingbetween the first plurality of UEs and the Core Network after the secondtime via the SV, the second earth station and a second network node,wherein the second signaling is transported between the SV and the firstplurality of UEs using the first plurality of radio cells.

In one implementation, a first network node configured for transferringsignaling for a first plurality of radio cells from a first earthstation to a second earth station, wherein the first plurality of radiocells is supported by a space vehicle (SV), the first network nodeincludes an external interface configured to communicate with a networknodes; at least one memory; at least one processor coupled to theexternal interface and the at least one memory, wherein the at least oneprocessor is configured to: transport, via the external interface, firstsignaling between a first plurality of User Equipments (UEs) and a CoreNetwork at a first time, and wherein the first signaling is transportedvia the SV, the first earth station and the first network node, whereinthe first signaling is transported between the SV and the firstplurality of UEs using the first plurality of radio cells; cease totransport the first signaling between the first plurality of UEs and theCore Network at a second time, wherein the second time is subsequent tothe first time; and enable the transport of second signaling between thefirst plurality of UEs and the Core Network after the second time viathe SV, the second earth station and a second network node, wherein thesecond signaling is transported between the SV and the first pluralityof UEs using the first plurality of radio cells.

In one implementation, a first network node configured for transferringsignaling for a first plurality of radio cells from a first earthstation to a second earth station, wherein the first plurality of radiocells is supported by a space vehicle (SV), the first network nodeincludes means for transporting first signaling between a firstplurality of User Equipments (UEs) and a Core Network at a first time,and wherein the first signaling is transported via the SV, the firstearth station and the first network node, wherein the first signaling istransported between the SV and the first plurality of UEs using thefirst plurality of radio cells; means for ceasing to transport the firstsignaling between the first plurality of UEs and the Core Network at asecond time, wherein the second time is subsequent to the first time;and means for enabling the transport of second signaling between thefirst plurality of UEs and the Core Network after the second time viathe SV, the second earth station and a second network node, wherein thesecond signaling is transported between the SV and the first pluralityof UEs using the first plurality of radio cells.

In one implementation, a non-transitory storage medium including programcode stored thereon, the program code is operable to configure at leastone processor in a first network node for transferring signaling for afirst plurality of radio cells from a first earth station to a secondearth station, wherein the first plurality of radio cells is supportedby a space vehicle (SV), the first network node includes program code totransport first signaling between a first plurality of User Equipments(UEs) and a Core Network at a first time, and wherein the firstsignaling is transported via the SV, the first earth station and thefirst network node, wherein the first signaling is transported betweenthe SV and the first plurality of UEs using the first plurality of radiocells; program code to cease to transport the first signaling betweenthe first plurality of UEs and the Core Network at a second time,wherein the second time is subsequent to the first time; and programcode to enabling the transport of second signaling between the firstplurality of UEs and the Core Network after the second time via the SV,the second earth station and a second network node, wherein the secondsignaling is transported between the SV and the first plurality of UEsusing the first plurality of radio cells.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a diagram of a communication system with a networkarchitecture having transparent space vehicles (SVs) that is capable ofsupporting satellite access to a wireless network.

FIG. 2 shows a diagram of a communication system with a networkarchitecture having regenerative SVs that is capable of supportingsatellite access to a wireless network.

FIG. 3 shows a diagram of a communication system with a networkarchitecture having regenerative SVs and a split satellite Node B (sNB)architecture that is capable of supporting satellite access to awireless network.

FIG. 4 illustrates a SV generating multiple beams over an area thatincludes multiple countries.

FIG. 5 illustrates radio cells produced by an SV over an area thatincludes a number of fixed cells.

FIG. 6 illustrates an assignment of radio cells produced by an SV tofixed tracking areas (TAs).

FIG. 7 is a diagram illustrating one implementation of defining a numberof rectangular fixed cells and fixed TAs in a geographic area using aplurality of center cell grid points and an array of fine grid points.

FIG. 8 is a diagram illustrating one implementation of defining a numberof hexagonal fixed cells and fixed TAs in a geographic area using aplurality of center cell grid points and an array of fine grid points.

FIG. 9 illustrates a number of cell center grid points and a rectangularfixed cell.

FIG. 10 illustrates a number of cell center grid points and a hexagonalfixed cell.

FIG. 11 is a diagram illustrating one implementation of specifying anumber of rectangular fixed cells and a fixed TA defined in a geographicarea by a plurality of center cell grid points.

FIG. 12 is a diagram illustrating one implementation of specifying anumber of rectangular fixed cells and a fixed TA defined in a geographicarea by a plurality of center cell grid points.

FIG. 13 is a diagram illustrating one implementation of specifying anumber of hexagonal fixed cells and a fixed TA defined in a geographicarea by a plurality of center cell grid points.

FIG. 14 is a diagram illustrating one implementation of specifying anumber of hexagonal fixed cells and a fixed TA defined in a geographicarea by a plurality of center cell grid points.

FIG. 15 is a diagram illustrating one implementation of specifying anumber of hexagonal fixed cells and a fixed TA defined in a geographicarea by a plurality of center cell grid points and an array of fine gridpoints.

FIG. 16 is a diagram illustrating one implementation of specifying anumber of hexagonal fixed cells and an irregular fixed TA defined in ageographic area by a plurality of center cell grid points.

FIG. 17 shows a number of cell center grid points and a UE andillustrates determining the closest cell center grid point for fixedcell determination.

FIG. 18 shows a number of fine grid points and an irregular fixed TA andillustrates determining the closest grid point for fixed TAdetermination.

FIG. 19 illustrates an example of a table that includes a compresseddescription of fixed cell and fixed TA information.

FIG. 20 shows a number of grid points and one implementation ofdetermining a closest grid point based on location of a user equipment(UE).

FIGS. 21A and 21B are diagrams illustrating implementations ofindependently defining fixed cells and fixed TAs in a geographic area inwhich TA color codes are used to define unique cell portions.

FIG. 22 shows a signaling flow that illustrates various messages sent tosupport UE access to a serving public land mobile networks (PLMN)through SVs using fixed cells and fixed TAs that are independentlydefined.

FIG. 23 is a block diagram illustrating a communication system andintra-sNB radio cell transfer between earth stations for a transparentSV.

FIG. 24 is a block diagram illustrating a communication system andinter-sNB radio cell transfer between earth stations for a transparentSV.

FIG. 25 is a block diagram illustrating a communication system andinter-PLMN radio cell transfer between earth stations for a transparentSV.

FIG. 26 is a block diagram illustrating a communication system andtransfer of a regenerative SV between earth stations with no change incore network.

FIG. 27 is a block diagram illustrating a communication system andtransfer of a regenerative SV between earth stations with a change incore network.

FIG. 28 is a block diagram illustrating control plane protocol layeringbetween a UE, a regenerative SV, an earth station, and a core network.

FIG. 29 is a block diagram illustrating user plane protocol layeringbetween a UE, a regenerative SV, an earth station, and a core network.

FIG. 30 shows a signaling flow illustrating various messages sentbetween entities of a communication network for the transfer ofregenerative SVs between earth stations acting as L1 Relays.

FIG. 31 shows a signaling flow illustrating various messages sentbetween entities of a communication network for the transfer ofregenerative SVs between earth stations acting as L2 Relays.

FIG. 32 is a block diagram illustrating a communication system andtransfer of a regenerative SV between earth stations with a splitarchitecture and with no change in a core network or in a Central Unit.

FIG. 33 is a block diagram illustrating a communication system andtransfer of a regenerative SV between earth stations with a splitarchitecture and with no change in a core network but with a change ofCentral Unit.

FIG. 34 is a block diagram illustrating control plane protocol layeringbetween a UE, a regenerative SV, an earth station, and a core networkwith a split architecture.

FIG. 35 is a block diagram illustrating user plane protocol layeringbetween a UE, a regenerative SV, an earth station, and a core networkwith a split architecture.

FIG. 36A shows a signaling flow illustrating various messages sentbetween entities of a communication network for the transfer ofregenerative SVs between earth stations and between Central Units with asplit architecture.

FIG. 36B shows a signaling flow illustrating a high level procedure tosupport UEs which are accessing radio cells supported by a transparentor regenerative SV when the SV is transferred between earth stations.

FIG. 37A shows a signaling flow illustrating various messages sentbetween entities of a communication network for a procedure for initialcore network access by a UE.

FIG. 37B shows another signaling flow illustrating various messages sentbetween entities of a communication network for a procedure for initialcore network access by a UE.

FIG. 38 shows a signaling flow illustrating various messages sentbetween entities of a communication network for an indication of aduration of service.

FIG. 39 is a diagram illustrating an example of a hardwareimplementation of a UE configured to access a serving PLMN through SVsas discussed herein.

FIG. 40 is a diagram illustrating an example of one or more componentsor modules of program code that when implemented by the one or moreprocessors in the UE configures the UE to access a serving PLMN throughSVs as discussed herein.

FIG. 41 is a diagram illustrating an example of a hardwareimplementation of a satellite NodeB (sNB) configured to support UEaccess to a serving PLMN through SVs as discussed herein.

FIG. 42 is a diagram illustrating an example of one or more componentsor modules of program code that when implemented by the one or moreprocessors in the sNB configures the sNB to support UE access to aserving PLMN through SVs as discussed herein.

FIG. 43 is a diagram illustrating an example of a hardwareimplementation of an SV configured to support UE access to a servingPLMN through SVs as discussed herein.

FIG. 44 is a diagram illustrating an example of one or more componentsor modules of program code that when implemented by the one or moreprocessors in the SV configures the SV to support UE access to a servingPLMN through SVs as discussed herein.

FIG. 45 is a diagram illustrating an example of a hardwareimplementation of a core network entity, such as an access and mobilitymanagement function (AMF) or a Location Management Function (LMF)configured to support UE access to a serving PLMN through SVs asdiscussed herein.

FIG. 46 is a diagram illustrating an example of one or more componentsor modules of program code that when implemented by the one or moreprocessors in the core network entity configures the core network entityto support UE access to a serving PLMN through SVs as discussed herein.

FIG. 47 is a flowchart of an example procedure performed by a UE foraccess to a serving PLMN through SVs as discussed herein.

FIG. 48 is a flowchart of an example procedure performed by a networknode to support UE access to a serving PLMN through SVs as discussedherein.

FIG. 49 is a flowchart of an example procedure performed by a networkentity to support UE access to a serving PLMN through SVs as discussedherein.

FIG. 50 is a flowchart of an example procedure performed by a networkentity to transfer signaling for radio cells supported by a spacevehicle from a first earth station to a second earth station asdiscussed herein.

FIG. 51 shows a flowchart of an example procedure performed by a UE forsupporting access by the UE via an SV to a serving PLMN.

FIG. 52 shows a flowchart of an example procedure performed by an sNBfor supporting access by a UE via a SV to a serving PLMN.

FIG. 53 shows a flowchart of an example procedure performed by an Accessand Mobility management Function (AMF) for supporting access by a UE viaa SV to a serving PLMN.

FIG. 54 shows a flowchart of an example procedure performed by asatellite Node B (sNB) to assist wireless access by user equipments(UEs) to serving Public Land Mobile Networks (PLMNs) via space vehicles(SVs).

FIG. 55 shows a flowchart of an example procedure performed by asatellite Node B (sNB) to assist wireless access by user equipments(UEs) to serving Public Land Mobile Networks (PLMs) via space vehicles(SVs).

FIG. 56 shows a flowchart of an example procedure performed by a userequipment (UE) to assist wireless access by the UE to a serving PublicLand Mobile Network (PLMN) via space vehicles (SVs).

FIG. 57 shows a flowchart of an example procedure performed by a userequipment (UE) to assist wireless access by the UE to a serving PublicLand Mobile Network (PLMN) via space vehicles (SVs).

Like reference symbols in the various drawings indicate like elements,in accordance with certain example implementations. In addition,multiple instances of an element may be indicated by following a firstnumber for the element with a letter or a hyphen and a second number.For example, multiple instances of an element 102 may be indicated as102-1, 102-2, 102-3 etc. When referring to such an element using onlythe first number, any instance of the element is to be understood (e.g.element 102 in the previous example would refer to elements 102-1,102-2, 102-3).

DETAILED DESCRIPTION

Satellites, also referred to as space vehicles (SVs) or communicationsatellites, may be used in communication systems, for example, usinggateways and one or more satellites to relay communication signalsbetween the gateways and one or more UEs. A UE, for example, may accessa satellite (instead of a terrestrial base station) which may beconnected to an earth station (ES), which is also referred to as aground station or non-terrestrial network (NTN) gateway. The earthstation in turn would connect to an element in a 5G Network such as amodified base station (e.g. without a terrestrial antenna) or a networknode in a 5G Core Network (5GCN). This element would in turn provideaccess to other elements in the 5G Network and ultimately to entitiesexternal to the 5G Network such as Internet web servers and other userdevices.

A rationale for 5G (or other cellular network) satellite access for UEsmay include ubiquitous outdoor coverage for both users and MobileNetwork Operators (MNOs). For example, in many countries, including theUnited States, unavailable or poor cellular coverage is a commonproblem. Moreover, cellular access is not always possible even whenthere is normally good cellular coverage. For example, cellular accessmay be hampered due to congestion, physical obstacles, a local cellularoutage caused by weather (e.g. a hurricane or tornado), or a local poweroutage. Satellite access to cellular networks could provide a newindependent access potentially available everywhere outdoors. Currentsatellite capable phones for low Earth orbit (LEO) SVs may be of similarsize to a cellular smartphone and, thus, mobile NR support withsatellite capable phones need not produce a significant increase in thesize of phones. Moreover, satellite capable smartphones may help drivehandset sales, and may add revenue for carriers. Potential users, forexample, may include anyone with limited or no cellular access, anyonewanting a backup to a lack of cellular access, and anyone involved inpublic safety or who otherwise needs (nearly) 100% reliable mobilecommunication. Additionally, some users may desire an improved or morereliable E911 service, e.g., for a medical emergency or vehicle troublein remote areas.

The use of 5G satellite access may provide other benefits. For example,5G satellite access may reduce Mobile Network Operation (MNO)infrastructure cost. For example, an MNO may use satellite access toreduce terrestrial base stations, such as NR NodeBs, also referred to asgNBs, and backhaul deployment in sparsely populated areas. Further, 5Gsatellite access may be used to overcome Internet blockage, e.g., incertain countries. Additionally, 5G satellite access may providediversification to Space Vehicle Operators (SVOs). For example, 5G NRsatellite access could provide another revenue stream to SVOs who wouldotherwise provide fixed Internet access.

Mobile wireless access for a UE to a 5G core network (5GCN) may besupported using low Earth orbit (LEO) and Geostationary Earth Orbiting(GEO) satellites. In one implementation, UE access to a 5GCN viacommunication satellites is supported using fixed tracking areas (TAs)and fixed cells, which may be defined using a rectangular or hexagonalarray of grid points. Fixed cells may be referred to as virtual cells orearth fixed cells. Fixed TAs may similarly be referred to as virtualTAs, earth fixed TAs or simply as TAs.

Alignment of fixed TAs and fixed cells may be problematic. For example,one concern may be an ability to exactly align the border of a cell orTA with the border of a country or some other area of significance (e.g.the border of a licensed coverage area for a 5GCN). Such alignment maybe critical to ensuring that a UE near the border of a country will onlyaccess a 5GCN in the same country as the UE and not a 5GCN in a nearbycountry. Similarly, a UE may only be allowed to access a 5GCN withinwhose coverage area the UE is currently located and not a 5GCN with anearby coverage area which does not include the location of the UE.

Solutions to these problems may be possible by defining fixed cells andfixed TAs using copious information and extra complexity. However,solutions that use a small amount of information and that reduce UE andnetwork impacts could be more desirable.

In one solution, referred to herein as “SOLUTION 1”, fixed cells andfixed TAs may be defined using grid points, but the definition of thefixed cells and fixed TAs may be independent and not require that eachfixed cell belong to just one TA. Such a solution may simplify thedefinition of fixed cells and fixed TAs because it may allow the use ofindependent grid point arrays in the definition of each and, in the caseof fixed TAs, may allow an alternative definition using polygons definedby the coordinates of a sequence of vertices. These definitions may besimple and, in the case of grid points, require only a small amount ofinformation. The definitions may then enable a UE or a network todetermine a current fixed TA and/or a current fixed cell for a UE basedon a known UE geographic location and fairly simply. A current fixedcell or a current fixed TA for a UE may be subsequently used (e.g. by a5GCN) to support regulatory services for a UE, such as EM calls, LIand/or WEA, in a similar manner as for UEs with 5G terrestrial access,and with minimal additional impact.

However, it may be desirable in some cases that a fixed cell belonguniquely to only one fixed TA. For example, at the border of a country,there may be a fixed cell whose coverage area includes part of a TA inone country and part of another TA in a different country. In such aninstance, it may be preferable or critical that the fixed cell belong toonly one of these TAs and one country (e.g. in order to avoid routing anemergency call to a PSAP in the wrong country). Accordingly, in oneimplementation of SOLUTION 1, cell coverage areas may be partitionedinto separate portions, each of which belongs to only one TA. Theresulting separate cell portions may then be treated as a new set ofcells, with the required property of each belonging to only one TA. Inone implementation, the cells may be identified by assigning each TA acolor code, such that any pair of TAs with a common border or commonvertex have different color codes. With this arrangement, a cell ID maybe extended with a color code ID for any TA for which the cell and TAcoverage areas overlap. The resulting extended cell ID may be treated asthe ID for the cell portion (i.e. the new cell) which overlaps with theTA coverage area.

As an example of the implementation of SOLUTION 1, assume that a cell Chas a coverage area that overlaps with the coverage areas of two TAs,denoted as TA1 and TA2. The ID for cell C would then be associated withTA1 and TA2. Now assume that C1 and C2 are two new cells whose coverageareas are the overlap of cell C with TA1 and TA2, respectively. Assumethat the color codes for TA1 and TA2 are cc1 and cc2, respectively andthat the cell ID for Cell C is C-ID, where c1, cc2 and C-ID eachrepresent bit strings. Extended cell IDs which are unique may be createdby extending the bits string for the cell ID with the bit strings forthe color codes, which produces extended cell IDs for cells C1 and C2which are C-IDcc1 and C-IDcc2, respectively. Similar extended cell IDsmay be created for other cells which overlap with two or more TAs. Forcells which overlap with only one TA, the extension may be performedusing just the color code for the one TA. The total number of bits ineach extended cell ID may be arranged to equal a standard 5G cell IDsize of 36 bits. The result can be a set of cells with unique extendedcell IDs which belong to just one TA each. However, the definition ofthe cells and TAs has still been simplified by temporarily abandoningthe one TA per cell principle.

With low earth orbit (LEO) SVs, an SV and radio cells supported by theSV may need to be handed off from a first earth station (ES) to a secondES as the SV ceases to have line of sight (LOS) communication with thefirst ES and starts to have LOS communication with the second ES. AnyUEs currently accessing the SV might also need to continue accessing theSV during and after the handover. This problem is already solved forexisting satellite telephone and data networks which do not emulate acellular network. However, it may be desirable to support satelliteaccess to 5G cellular networks in a manner which minimizes new impactsto UEs and existing 5G networks by making satellite access appear to bea new type of terrestrial RAT. For example, while radio cells supportedby a LEO SV will be continually moving over the Earth's surface,terrestrial 5G networks are designed to use cells and tracking areaswhose coverage areas never move. This adds an extra layer of complexityto support of SV and radio cell handover for which existing solutionswere not defined. As an example of this extra complexity, the handoverof an SV from a first ES to a second ES may also need to supporthandover to a new 5G base station and/or new 5G core network.

Implementations described later herein, and referred to as “SOLUTION 2”,may support handover of both transparent SVs and regenerative SVs from afirst earth station to a second earth station. Transparent SVs relaycommunications between fixed terrestrial 5G base stations (referred toas sNBs) and UEs. Regenerative SVs include the functional capability ofeither a whole sNB or part of an sNB and relay communication between a5G Core Network (5GCN) and UEs. A handover of an SV may transfer an SVfrom one earth station to another and may also transfer the SV from onesNB to another sNB and/or from one 5GCN to another 5GCN. The handovermay allow UEs to continue to access the SV before, during and after thehandover with limited interruption of voice, data and signalingcommunication.

Another problem in supporting 5G satellite access to 5GCNs is that aradio coverage area of an SV may be very large and/or may be difficultto precisely control. Further the radio coverage area may move, forexample with a LEO SV. Consequently, the radio coverage area of an SVmay include parts of two or more countries at the same time. In thissituation, two UEs in different countries may both be able to access theSV at the same time. Further, it may be required that signaling for eachUE be routed to a 5GCN in the same country as the UE and not in adifferent country. Alternatively, it may be required that signaling besupported for UEs in only one country and that UEs in other countriesnot be allowed to access the SV. These requirements may be associatedwith how UEs are permitted (e.g. by national regulators) to access a 5Gnetwork using SVs. Solutions applicable to current 5G terrestrial accessmay not support these requirements as they are based on fixed cellularaccess with each cell belonging to one (known) country. Solutions forexisting SV telephony and data access may also not be applicable becausethey do not support access to cellular networks in a manner compatiblewith terrestrial cellular access.

Implementations described later herein, and referred to as “SOLUTION 3”,can provide a solution to the above problems and may reuse existing 5Gnetwork access procedures with only small impacts. The implementationscan also support mobility management of UEs (e.g. periodic registration)which are accessing SVs with only small impacts to existing procedures.

In the description below, different aspects of SOLUTION 1 are describedwith reference primarily to FIGS. 7-22 and FIGS. 47-49. Differentaspects of SOLUTION 2 are described with reference primarily to FIGS.23-36 and FIG. 50. Different aspects of SOLUTION 3 are described withreference primarily to FIGS. 37 and 38 and FIGS. 51-57.

Another problem with SV access to core networks, such as a 5GCN, is thatan SV may be accessible for only a limited time and a UE may be requiredto periodically handover to a new SV and/or a new terrestrial radionode. For example, with LEO SVs, an SV would typically be accessiblefrom any fixed location for around 3 to 15 minutes, depending on theheight of the SV and the perpendicular distance (measured over theEarth's surface) between the fixed location and the orbital plane of theSV. Following this period of accessibility, a UE that was accessing theSV, or just camped on a radio cell for the SV, would need to handover toanother SV or camp on another SV in each case, respectively. Similarly,following a period of accessibility of an SV to an earth station, the SVitself and any UEs still accessing the SV would need to undergo handover(or transfer) to another earth station. However, sometimes handover ortransfer of UEs to a new earth station may not be possible or may not beallowed, e.g., if the new earth station is in a different country thanthe country in which the UEs are located or connects to a different corenetwork than the core network with which the UEs are registered. Incases such as these, the UEs would need to be handed off to a differentSV before the SV itself is handed off or transferred to a new earthstation. From the perspective of a UE, these handover or transfer eventsmay be sudden and disruptive to communication, e.g., if a new SV cannotbe found before the UE needs to cease access to a current SV. Inaddition, from a network perspective, the handover of a large numbers ofUEs from one SV to another at about the same time may impose anunacceptable system load. Methods to avoid these consequences aretherefore desirable.

In one implementation, as described herein, a solution may be based onpredicting an SV orbital motion in advance. Knowing the future locationsof an SV, it may be possible to determine in advance the duration ofradio coverage by the SV for any location on the Earth and the durationof accessibility by the SV to any earth station. For example,determining the duration of radio coverage by an SV and the duration ofaccessibility by the SV to an earth station may take into account theradio cells supported by the SV including the coverage areas of theseradio cells and whether steerable and directional antennas are used bythe SV to maintain coverage for the same geographic area by a radio cellover an extended period. With this information, it may be possible todetermine: (1) a period of time (e.g. start time and end time) duringwhich an SV will be using a particular earth station; and (2) a periodof time (e.g. start time and end time) during which a particular radiocell for an SV will be providing radio coverage for part or all of anyfixed TA.

In instances where all UEs will be handed off from a current SV to a new(different) SV prior to the current SV itself being handed off to a newearth station, the current SV may provide an advance indication to UEsof the impending handover, based on the information in (1), i.e., theperiod of time during which an SV will be using a particular earthstation. With this information, UEs in connected mode may search forother SVs (e.g. and provide measurements to assist handover) and UEs inidle mode may find another SV to camp on. Similarly, an SV may providean advance indication to UEs in idle mode and located in a particular TAthat radio cell coverage of the TA by the SV will cease at some imminentfuture time, as determined according to the information in (2), i.e.,the period of time during which a particular radio cell for an SV willbe providing radio coverage for part or all of a fixed network TA. Withthis information, the UEs may find another SV, before coverage from thecurrent SV ceases.

In some implementations, the advance indications may be provided usingSystem Information Blocks (SIBs) such as SIB1 or SIB2. For example, aSIB1 or SIB2 for a particular radio cell supported by an SV may includeone or more of the radio cell remaining lifetime (e.g. a value in therange 0-1023 seconds); a list of TAs supported by the radio cell; andfor each supported TA, a remaining lifetime of radio coverage of the TAby the radio cell; or a combination thereof. Such indications are notprovided for terrestrial radio cells because the coverage areas do notmove and terrestrial base stations are not themselves subject tohandover. However, this extra information for UEs accessing a corenetwork through SVs may be advantageous to avoid the type of problemsdescribed above.

FIG. 1 shows a diagram of a communication system 100 capable ofsupporting satellite access using 5G New Radio (NR) or some otherwireless access type such as Code Division Multiple Access (CDMA),according to an embodiment. FIG. 1 illustrates a network architecturewith transparent space vehicles (SVs). A transparent SV may implementfrequency conversion and a radio frequency (RF) amplifier in both uplink(UL) and downlink (DL) directions and may correspond to an analog RFrepeater. A transparent SV, for example, may receive uplink (UL) signalsfrom all served UEs and may redirect the combined signals DL to an ESwithout demodulating or decoding the signals. Similarly, a transparentSV may receive an UL signal from an ES and redirect the signal DL toserved UEs without demodulating or decoding the signal. However, the SVmay frequency convert received signals and may amplify and/or filterreceived signals before transmitting the signals.

The communication system 100 comprises a number of UEs 105, a number ofSVs 102-1 to 102-4 (collectively referred to herein as SVs 102), anumber of Non-Terrestrial Network (NTN) gateways 104-1 to 104-4(collectively referred to herein as NTN gateways 104) (sometimesreferred to herein simply as gateways 104, earth stations 104, or groundstations 104), a number of gNBs capable of communication with UEs viaSVs 102 referred to herein as satellite NodeBs (sNBs) 106-1 to 106-3(collectively referred to herein as sNBs 106). It is noted that the termsNB refers in general to an enhanced gNB with support for SVs and may bereferred to as a gNB (e.g. in 3GPP). The communication system 100 isillustrated as further including components of a number of FifthGeneration (5G) networks including 5G Core Networks (5GCNs) 110-1 to110-3 (collectively referred to herein as 5GCNs 110). The 5GCNs 110 maybe public land mobile networks (PLMN) that may be located in the same orin different countries. FIG. 1 illustrates various components within5GCN1 110-1 and a Next Generation (NG) Radio Access Network (RAN)(NG-RAN) 112 that may operate with 5GCN1 110-1. It should be understoodthat 5GCN2 110-2 and 5GCN3 110-3 may include identical, similar ordifferent components and associated NG-RANs, which are not illustratedin FIG. 1 in order to avoid unnecessary obfuscation. A 5G network mayalso be referred to as a New Radio (NR) network; NG-RAN 112 may bereferred to as a 5G RAN or as an NR RAN; and 5GCN 110 may be referred toas an NG Core network (NGC).

The communication system 100 may further utilize information from spacevehicles (SVs) 190 for Satellite Positioning System (SPS) includingGlobal Navigation Satellite Systems (GNSS) like Global PositioningSystem (GPS), GLObal NAvigation Satellite System (GLONASS), Galileo orBeidou or some other local or regional SPS, such as Indian RegionalNavigation Satellite System (IRNSS), European Geostationary NavigationOverlay Service (EGNOS), or Wide Area Augmentation System (WAAS), all ofwhich are sometimes referred to herein as GNSS. It is noted that SVs 190act as navigation SVs and are separate and distinct from SVs 102, whichact as communication SVs. However, it is not precluded that some of SVs190 may also act as some of SVs 102 and/or that some of SVs 102 may alsoact as some of SVs 190. In some implementations, for example, the SVs102 may be used for both communication and positioning. Additionalcomponents of the communication system 100 are described below. Thecommunication system 100 may include additional or alternativecomponents.

Permitted connections in the communication system 100 having the networkarchitecture with transparent SVs illustrated in FIG. 1, allow an sNB106 to access multiple Earth stations 104 and/or multiple SVs 102. OnesNB 106 may also be shared by multiple PLMNs (5GCNs 110), which may allbe in the same country or possibly in different countries, and one Earthstation 104 may be shared by more than one sNB 106.

It should be noted that FIG. 1 provides only a generalized illustrationof various components, any or all of which may be utilized asappropriate, and each of which may be duplicated or omitted asnecessary. Specifically, although only three UEs 105 are illustrated, itwill be understood that many UEs (e.g., hundreds, thousands, millions,etc.) may utilize the communication system 100. Similarly, thecommunication system 100 may include a larger (or smaller) number of SVs190, SVs 102, earth stations 104, sNBs 106, NG-RAN 112, gNBs 114, 5GCNs110, external clients 140, and/or other components. The illustratedconnections that connect the various components in the communicationsystem 100 include data and signaling connections which may includeadditional (intermediary) components, direct or indirect physical and/orwireless connections, and/or additional networks. Furthermore,components may be rearranged, combined, separated, substituted, and/oromitted, depending on desired functionality.

While FIG. 1 illustrates a 5G-based network, similar networkimplementations and configurations may be used for other communicationtechnologies, such as 3G, 4G Long Term Evolution (LTE), etc.

The UE 105 may comprise and/or be referred to as a device, a mobiledevice, a wireless device, a mobile terminal, a terminal, a mobilestation (MS), a Secure User Plane Location (SUPL) Enabled Terminal(SET), or by some other name. Moreover, UE 105 may correspond to acellphone, smartphone, laptop, tablet, PDA, tracking device, navigationdevice, Internet of Things (IoT) device, or some other portable ormoveable device. Typically, though not necessarily, the UE 105 maysupport wireless communication using one or more Radio AccessTechnologies (RATs) such as using Global System for Mobile communication(GSM), Code Division Multiple Access (CDMA), Wideband CDMA (WCDMA), LTE,High Rate Packet Data (HRPD), IEEE 802.11 WiFi (also referred to asWi-Fi), Bluetooth® (BT), Worldwide Interoperability for Microwave Access(WiMAX), 5G New Radio (NR) (e.g., using the NG-RAN 112 and 5GCN 140),etc. The UE 105 may also support wireless communication using a WirelessLocal Area Network (WLAN) which may connect to other networks (e.g. theInternet) using a Digital Subscriber Line (DSL) or packet cable forexample. The UE 105 further supports wireless communications using spacevehicles, such as SVs 102. The use of one or more of these RATs mayallow the UE 105 to communicate with an external client 140 (viaelements of 5GCN 110 not shown in FIG. 1, or possibly via a GatewayMobile Location Center (GMLC) 126).

The UE 105 may include a single entity or may include multiple entitiessuch as in a personal area network where a user may employ audio, videoand/or data I/O devices and/or body sensors and a separate wireline orwireless modem.

The UE 105 may support position determination, e.g., using signals andinformation from space vehicles 190 in an SPS, such as GPS, GLONASS,Galileo or Beidou or some other local or regional SPS such as IRNSS,EGNOS or WAAS, all of which may be generally referred to herein as GNSS.Position measurements using SPS are based on measurements of propagationdelay times of SPS signals broadcast from a number of orbitingsatellites to a SPS receiver in the UE 105. Once the SPS receiver hasmeasured the signal propagation delays for each satellite, the range toeach satellite may be determined and precise navigation informationincluding 3-dimensional position, velocity and time of day of the SPSreceiver may then be determined using the measured ranges and the knownlocations of the satellites. Positioning methods which may be supportedusing SVs 190 may include Assisted GNSS (A-GNSS), Real Time Kinematic(RTK), Precise Point Positioning (PPP) and Differential GNSS (DGNSS).Information and signals from SVs 102 may also be used to supportpositioning. The UE 105 may further support positioning usingterrestrial positioning methods, such as Observed Time Difference ofArrival (OTDOA), Enhanced Cell ID (ECID), Round Trip signal propagationTime (RTT), multi-cell RTT, angle of arrival (AOA), angle of departure(AOD), time of arrival (TOA), receive-transmit transmission-timedifference (Rx-Tx) and/or other positioning methods.

An estimate of a location of the UE 105 may be referred to as alocation, location estimate, location fix, fix, position, positionestimate or position fix, and may be geographic, thus providing locationcoordinates for the UE 105 (e.g., latitude and longitude) which may ormay not include an altitude component (e.g., height above sea level,height above or depth below ground level, floor level or basementlevel). Alternatively, a location of the UE 105 may be expressed as acivic location (e.g., as a postal address or the designation of somepoint or small area in a building such as a particular room or floor). Alocation of the UE 105 may also be expressed as an area or volume(defined either geographically or in civic form) within which the UE 105is expected to be located with some probability or confidence level(e.g., 67%, 95%, etc.) A location of the UE 105 may further be arelative location comprising, for example, a distance and direction orrelative X, Y (and Z) coordinates defined relative to some origin at aknown location which may be defined geographically, in civic terms, orby reference to a point, area, or volume indicated on a map, floor planor building plan. In the description contained herein, the use of theterm location may comprise any of these variants unless indicatedotherwise. When computing the location of a UE, it is common to solvefor local x, y, and possibly z coordinates and then, if needed, convertthe local coordinates into absolute ones (e.g. for latitude, longitudeand altitude above or below mean sea level).

The UEs 105 are configured to communicate with 5GCNs 110 via the SVs102, earth stations 104, and sNBs 106. As illustrated by NG-RAN 112, theNG-RANs associated with the 5GCNs 110 may include one or more sNBs 106.The NG-RAN 112 may further include a number of terrestrial basestations, such as gNB 114. Pairs of terrestrial and/or satellite basestations, e.g., gNBs 114 and sNB 106-1 in NG-RAN 112 may be connected toone another using terrestrial links—e.g. directly as shown in FIG. 1 orindirectly via other gNBs 114 or sNBs 106 and communicate using an Xninterface. Access to the 5G network is provided to UEs 105 via wirelesscommunication between each UE 105 and a serving sNB 106, via an SV 102and an earth station 104. The sNBs 106 may provide wirelesscommunications access to the 5GCN 110 on behalf of each UE 105 using 5GNR. 5G NR radio access may also be referred to as NR radio access or as5G radio access and may be as defined by the Third GenerationPartnership Project (3GPP).

Base stations (BSs) in the NG-RAN 112 shown in FIG. 1 may also orinstead include a next generation evolved Node B, also referred to as anng-eNB. An ng-eNB may be connected to one or more sNBs 106 and/or gNBs114 in NG-RAN 112—e.g. directly or indirectly via other sNBs 106, gNBs114 and/or other ng-eNBs. An ng-eNB may provide LTE wireless accessand/or evolved LTE (eLTE) wireless access to a UE 105.

An sNB 106 may be referred to by other names such as a gNB or a“satellite node” or “satellite access node.” The sNBs 106 are not thesame as terrestrial gNB 114, but may be based on a terrestrial gNB 114with additional capability. For example an sNB 106 may terminate theradio interface and associated radio interface protocols to UEs 105 andmay transmit DL signals to UEs 105 and receive UL signals from UEs 105via SVs 102 and ESs 104. An sNB 106 may also support signalingconnections and voice and data bearers to UEs 105 and may supporthandover of UEs 105 between different radio cells for the same SV 102,between different SVs 102 and/or between different sNBs 106. In somesystems, an sNB 106 may be referred to as a gNB or as an enhanced gNB.SNBs 106 may be configured to manage moving radio beams (for LEO SVs)and associated mobility of UEs 105. The sNBs 106 may assist in thehandover (or transfer) of SVs 102 between different Earth stations 104,different sNBs 106, and between different countries. The sNBs 106 mayhide or obscure specific aspects of connected SVs 102 from the 5GCN 110,e.g. by interfacing to a 5GCN 110 in the same way or in a similar way toa gNB 114, and may avoid a 5GCN 110 from having to maintainconfiguration information for SVs 102 or perform mobility managementrelated to SVs 102. The sNBs 106 may further assist in sharing of SVs102 over multiple countries. The sNBs 106 may communicate with one ormore earth stations 104, e.g., as illustrated by sNB 106-2 communicatingwith earth stations 104-2 and 104-1. The sNBs 106 may be separate fromearth stations 104, e.g., as illustrated by sNBs 106-1 and 106-2, andearth stations 104-1 and 104-2. The sNBs 106 may include or may becombined with one or more earth stations 104, e.g., using a splitarchitecture. For example, sNB 106-3 is illustrated with a splitarchitecture, with an sNB central unit (sNB-CU) 107 and the earthstations 104-3 and 104-4 acting as Distributed Units (DUs). An sNB 106may typically be fixed on the ground with transparent SV operation. Inone implementation, one sNB 106 may be physically combined with, orphysically connected to, one ES 104 to reduce complexity and cost.

The earth stations 104 may be shared by more than one sNB 106 and maycommunicate with UE 105 via the SVs 102. An earth station 104 may bededicated to just one SVO and to one associated constellation of SVs 102and hence may be owned and managed by the SVO. While earth stations 104may be included within an sNB 106, e.g., as an sNB-DU within sNB 106-3,this may only occur when the same SVO or the same MNO owns both the sNB106 and the included ESs 104. Earth stations 104 may communicate withSVs 102 using control and user plane protocols that may be proprietaryto an SVO. The control and user plane protocols between earth stations104 and SVs 102 may: (i) establish and release Earth Station 104 to SV102 communication links, including authentication and ciphering; (ii)update SV software and firmware; (iii) perform SV Operations andMaintenance (O&M); (iv) control radio beams (e.g., direction, power,on/off status) and mapping between radio beams and earth station uplink(UL) and downlink (DL) payload; and (v) assist with handoff of an SV 102or radio cell to another Earth station 104.

As noted, while FIG. 1 depicts nodes configured to communicate accordingto 5G NR and LTE communication protocols for an NG-RAN 112, nodesconfigured to communicate according to other communication protocols maybe used, such as, for example, an LTE protocol for an Evolved UniversalMobile Telecommunications System (UMTS) Terrestrial Radio Access Network(E-UTRAN) or an IEEE 802.11x protocol for a WLAN. For example, in a 4GEvolved Packet System (EPS) providing LTE wireless access to UE 105, aRAN may comprise an E-UTRAN, which may comprise base stations comprisingevolved Node Bs (eNBs) supporting LTE wireless access. A core networkfor EPS may comprise an Evolved Packet Core (EPC). An EPS may thencomprise an E-UTRAN plus EPC, where the E-UTRAN corresponds to NG-RAN112 and the EPC corresponds to 5GCN 110 in FIG. 1. The methods andtechniques described herein for support of a RAN location serverfunction may be applicable to such other networks.

The sNBs 106 and gNBs 114 may communicate with an Access and MobilityManagement Function (AMF) 122 in a 5GCN 110, which, for positioningfunctionality, may communicate with a Location Management Function (LMF)124. For example, the sNBs 106 may provide an N2 interface to the AMF122. An N2 interface between an sNB 106 and a 5GCN 110 may be the sameas an N2 interface supported between a gNB 114 and a 5GCN 110 forterrestrial NR access by a UE 105 and may use the Next GenerationApplication Protocol (NGAP) defined in 3GPP Technical Specification (TS)38.413 between an sNB 106 and the AMF 122. The AMF 122 may supportmobility of the UE 105, including cell change and handover and mayparticipate in supporting a signaling connection to the UE 105 andpossibly data and voice bearers for the UE 105. The LMF 124 may supportpositioning of the UE 105 when UE accesses the NG-RAN 112 and maysupport position procedures/methods such as A-GNSS, OTDOA, RTK, PPP,DGNSS, ECID, AOA, AOD, multi-cell RTT and/or other positioningprocedures including positioning procedures based on communicationsignals from one or more SVs 102. The LMF 124 may also process locationservices requests for the UE 105, e.g., received from the AMF 122 orfrom the GMLC 126. The LMF 124 may be connected to AMF 122 and/or toGMLC 126. In some embodiments, a node/system that implements the LMF 124may additionally or alternatively implement other types oflocation-support modules, such as an Enhanced Serving Mobile LocationCenter (E-SMLC). It is noted that in some embodiments, at least part ofthe positioning functionality (including derivation of a UE 105'slocation) may be performed at the UE 105 (e.g., using signalmeasurements obtained by UE 105 for signals transmitted by SVs 120, SVs190, gNBs 114 and assistance data provided to the UE 105, e.g. by LMF124).

The Gateway Mobile Location Center (GMLC) 126 may support a locationrequest for the UE 105 received from an external client 140 and mayforward such a location request to the AMF 122 for forwarding by the AMF122 to the LMF 124 or may forward the location request directly to theLMF 124. A location response from the LMF 124 (e.g. containing alocation estimate for the UE 105) may be similarly returned to the GMLC126 either directly or via the AMF 122, and the GMLC 126 may then returnthe location response (e.g., containing the location estimate) to theexternal client 140. The GMLC 126 is shown connected to both the AMF 122and LMF 124 in FIG. 1 though only one of these connections may besupported by 5GCN 110 in some implementations.

A Network Exposure Function (NEF) 128 may be included in 5GCN 110. TheNEF 128 may support secure exposure of capabilities and eventsconcerning 5GCN 110 and UE 105 to an external client 140 and may enablesecure provision of information from external client 140 to 5GCN 110.

A User Plane Function (UPF) 130 may support voice and data bearers forUE 105 and may enable UE 105 voice and data access to other networkssuch as the Internet 175. The UPF 130 may be connected to sNBs 106 andgNBs 114. UPF 130 functions may include: external Protocol Data Unit(PDU) session point of interconnect to a Data Network, packet (e.g.Internet Protocol (IP)) routing and forwarding, packet inspection anduser plane part of policy rule enforcement, Quality of Service (QoS)handling for user plane, downlink packet buffering and downlink datanotification triggering. UPF 130 may be connected to a Secure User PlaneLocation (SUPL) Location Platform (SLP) 132 to enable support ofpositioning of UE 105 using SUPL. SLP 132 may be further connected to oraccessible from external client 140.

As illustrated, a Session Management Function (SMF) 134 connects to theAMF 122 and the UPF 130. The SMF 134 may have the capability to controlboth a local and a central UPF within a PDU session. SMF 134 may managethe establishment, modification and release of PDU sessions for UE 105,perform IP address allocation and management for UE 105, act as aDynamic Host Configuration Protocol (DHCP) server for UE 105, and selectand control a UPF 130 on behalf of UE 105.

The external client 140 may be connected to the core network 110 via theGMLC 126 and/or the SLP 132, and/or NEF 128. The external client 140 mayoptionally be connected to the core network 110 and/or to a locationserver, which may be, e.g., an SLP, that is external to 5GCN 110, viathe Internet 175. The external client 140 may be connected to the UPF130 directly (not shown in FIG. 1) or through the Internet 175. Theexternal client 140 may be a server, a web server, or a user device,such as a personal computer, a UE, etc.

As noted, while the communication system 100 is described in relation to5G technology, the communication system 100 may be implemented tosupport other communication technologies, such as GSM, WCDMA, LTE, etc.,that are used for supporting and interacting with mobile devices such asthe UE 105 (e.g., to implement voice, data, positioning, and otherfunctionalities). In some such embodiments, the 5GCN 110 may beconfigured to control different air interfaces. For example, in someembodiments, 5GCN 110 may be connected to a WLAN, either directly orusing a Non-3GPP InterWorking Function (N3IWF, not shown FIG. 1) in the5GCN 110. For example, the WLAN may support IEEE 802.11 WiFi access forUE 105 and may comprise one or more WiFi APs. Here, the N31WF mayconnect to the WLAN and to other elements in the 5GCN 110 such as AMF122.

Support of transparent SVs with the network architecture shown in FIG. 1may impact the communication system as follows. The 5GCN 110 may treat asatellite RAT as a new type of RAT (e.g. having longer delay, reducedbandwidth and higher error rate). Consequently, while there may be someimpact to Protocol Data Unit (PDU) session establishment and mobilitymanagement (MM) and connection management (CM) procedures, impacts to anAMF 122 (or LMF 124) may be small—e.g. such as providing pre-configureddata for fixed tracking areas (TAs) and cells to a UE 105 duringRegistration. There may be no impact to the SVs 102. The SVs 102 may beshared with other services (e.g. satellite TV, fixed Internet access)with 5G NR mobile access for UEs added in a transparent manner. This mayenable legacy SVs 102 to be used and may avoid the need to deploy a newtype of SV 102. Further, the sNBs 106 may be fixed and may be configuredto support one country and one or more PLMNs in that country. The sNBs106 may need to assist assignment and transfer of SVs 102 and radiocells between sNBs 106 and earth stations 104 and support handover ofUEs 105 between radio cells, SVs 102 and other sNBs 106. Thus, the sNB106 may differ from a terrestrial gNB 114. Additionally, a coverage areaof an sNB 106 may be much larger than the coverage area of a gNB 114.

In some implementations, the radio beam coverage of an SV 102 may belarge, e.g., up to or greater than 1000 kms across, and may provideaccess to more than one country. An earth station 104 may be shared bymultiple sNBs (e.g., earth station 104-1 may be shared by sNBs 106-1 and106-2), and an sNB 106 may be shared by multiple core networks inseparate PLMNs located in the same country or in different countries(e.g., sNB 106-2 may be shared by 5GCN1 110-1 and 5GCN2 110-1, which maybe in different PLMNs in the same country or in different countries).

FIG. 2 shows a diagram of a communication system 200 capable ofsupporting satellite access using 5G New Radio (NR) or some otherwireless access type such as Code Division Multiple Access (CDMA),according to an embodiment. The network architecture shown in FIG. 2 issimilar to that shown in FIG. 1, like designated elements being similaror the same. FIG. 2, however, illustrates a network architecture withregenerative SVs 202-1, 202-2, 202-3, and 202-4 (collectively SVs 202),as opposed to transparent SVs 102 shown in FIG. 1. A regenerative SV202, unlike a transparent SV 102, includes an on-board sNB 202 (or atleast the functional capabilities of an sNB), and is sometimes referredto herein as an SV/sNB 202. Reference to an sNB 202 is used herein whenreferring to SV/sNB 202 functions related to communication with UEs 105and 5GCNs 110, whereas reference to an SV 202 is used when referring toSV/sNB 202 functions related to communication with ESs 104 and with UEs105 at a physical radio frequency level. However, there may be noprecise delimitation of an SV 202 versus an sNB 202.

An onboard sNB 202 may perform many of the same functions as an sNB 106as described previously. For example, an sNB 202 may terminate the radiointerface and associated radio interface protocols to UEs 105 and maytransmit DL signals to UEs 105 and receive UL signals from UEs 105,which may include encoding and modulation of transmitted signals anddemodulation and decoding of received signals. An sNB 202 may alsosupport signaling connections and voice and data bearers to UEs 105 andmay support handover of UEs 105 between different radio cells for thesame sNB 202 and between different sNBs 202. The sNBs 202 may assist inthe handover (or transfer) of SVs 202 between different Earth stations104, different 5GCNs 110, and between different countries. The sNBs 202may hide or obscure specific aspects of SVs 202 from the 5GCN 110, e.g.by interfacing to a 5GCN 110 in the same way or in a similar way to agNB 114. The sNBs 202 may further assist in sharing of SVs 202 overmultiple countries. The sNBs 202 may communicate with one or more earthstations 104 and with one or more 5GCNs 110 via the ESs 104. In someimplementations, sNBs 202 may communicate directly with other sNBs 202using Inter-Satellite Links (ISLs) (not shown in FIG. 2), which maysupport an Xn interface between any pair of sNBs 202.

With LEO SVs, an SV/sNB 202 needs to manage moving radio cells withcoverage in different countries at different times. Earth stations 104may be connected directly to the 5GCN 110, as illustrated. For example,as illustrated, earth station 104-1 may be connected to AMF 122 and UPF130 of 5GCN1 110-1, while earth station 104-2 may be similarly connectedto 5GCN2 110-2, and earth stations 104-3 and 104-4 are connected to5GCN3 110-3. The earth stations 104 may be shared by multiple 5GCNs 110,for example, if Earth stations 104 are limited. For example, in someimplementations (illustrated with dotted lines), earth station 104-2 maybe connected to both 5GCN1 110-1 and 5GCN2 110-2, and earth station104-3 may be connected to both 5GCN2 110-2 and 5GCN3 110-3. The 5GCN 110may need to be aware of SV 202 coverage areas in order to page UEs 105and to manage handover. Thus, as may be seen, the network architecturewith regenerative SVs may have more impact and complexity with respectto both sNBs 202 and 5GCNs 110 than the network architecture withtransparent SVs 102 shown in FIG. 1.

Support of regenerative SVs with the network architecture shown in FIG.2 may impact the communication system 200 as follows. The 5GCN 110 maybe impacted if fixed TAs and fixed cells are not supported, since corecomponents of mobility management and regulatory services, which aretypically based on fixed cells and fixed TAs for terrestrial PLMNs,would have to be replaced by a new system (e.g. based on UE 105location). If fixed TAs and fixed cells are supported, a 5GCN 110 (e.g.the AMF 122) may need to map any fixed TA to one or SVs 202 with currentradio coverage of the TA when performing paging of a UE 105 that islocated in this TA. This could require configuration in the 5GCN 110 oflong term orbital data for SVs 202 (e.g. obtained from an SVO for SVs202) and could add significant new impact to a 5GCN 110.

Legacy SVs could need a substantial software (SW) update to support sNB202 functions, which may not be feasible. An SV 202 would also need tofully support all UEs 105 accessing the SV 202, which could beproblematic with a legacy SV due to limited processing and storagecapability. Hence, an SV 202 would probably need to comprise newhardware (HW) and SW rather than being based on a SW upgrade to anexisting SV. A new SV/sNB 202 may need to support regulatory and otherrequirements for multiple countries. A GEO SV 202 coverage area wouldtypically include several or many countries, whereas a LEO or mediumearth orbit (MEO) SV 202 would typically orbit over many countries.Support of fixed TAs and fixed cells may then require that a SV/sNB 202be configured with fixed TAs and fixed cells for an entire worldwidecoverage area. Alternatively, AMFs 122 (or LMFs 124) in individual 5GCNs110 could support fixed TAs and fixed cells for the associated PLMN toreduce SV/sNB 202 complexity and at the expense of more 5GCN 110complexity. Additionally, SV/sNB 202 to SV/sNB 202 ISLs would typicallychange dynamically as relative SV/sNB 202 positions change, making Xnrelated procedures more complex.

FIG. 3 shows a diagram of a communication system 300 capable ofsupporting satellite access using 5G New Radio (NR) or some otherwireless access type such as Code Division Multiple Access (CDMA),according to an embodiment. The network architecture shown in FIG. 3 issimilar to that shown in FIGS. 1 and 2, like designated elements beingsimilar or the same. FIG. 3, however, illustrates a network architecturewith regenerative SVs 302-1, 302-2, 302-3, and 302-4 (collectivelyreferred to as SVs 302), as opposed to transparent SVs 102 shown in FIG.1, and with a split architecture for the sNBs. A regenerative SV 302,unlike a transparent SV 102, includes an on-board sNB Distributed Unit(sNB-DU) 302, and is sometimes referred to herein as an SV/sNB-DU 302.Reference to an sNB-DU 302 is used herein when referring to SV/sNB 302functions related to communication with UEs 105 and sNB-CUs 307, whereasreference to an SV 302 is used when referring to SV/sNB-DU 302 functionsrelated to communication with ESs 104 and with UEs 105 at a physicalradio frequency level. However, there may be no precise delimitation ofan SV 302 versus an sNB-DU 302.

Each sNB-DU 302 communicates with one ground based sNB-CU 307 via one ormore ESs 104. One sNB-CU 307 together with the one or more sNB-DUs 302which are in communication with the sNB-CU 307 performs functions, andmay use internal communication protocols, which are similar to or thesame as a gNB with a split architecture as described in 3GPP TS 38.401.Here an sNB-DU 302 corresponds to and performs functions similar to orthe same as a gNB Distributed Unit (gNB-DU) defined in TS 38.401, whilean sNB-CU 307 corresponds to and performs functions similar to or thesame as a gNB Central Unit (gNB-CU) defined in TS 38.401. For example,an sNB-DU 302 and an sNB-CU 307 may communicate with one another usingan F1 Application Protocol (F1AP) as defined in 3GPP TS 38.473 andtogether may perform some or all of the same functions as an sNB 106 orsNB 202 as described previously. To simplify references to differenttypes of sNB is the description below, an sNB-DU 302 may sometimes bereferred to an sNB 302 (without the “DU” label), and an sNB-CU 307 maysometimes be referred to an sNB 307 (without the “CU” label).

An sNB-DU 302 may terminate the radio interface and associated lowerlevel radio interface protocols to UEs 105 and may transmit DL signalsto UEs 105 and receive UL signals from UEs 105, which may includeencoding and modulation of transmitted signals and demodulation anddecoding of received signals. An sNB-DU 302 may support and terminateRadio Link Control (RLC), Medium Access Control (MAC) and Physical (PHY)protocol layers for the NR Radio Frequency (RF) interface to UEs 105, asdefined in 3GPP TSs 38.201, 38.202, 38.211, 38.212, 38.213, 38.214,38.215, 38.321 and 38.322. The operation of an sNB-DU 302 is partlycontrolled by the associated sNB-CU 307. One sNB-DU 302 may support oneor more NR radio cells for UEs 105. An sNB-CU 307 may support andterminate a Radio Resource Control (RRC) protocol, Packet DataConvergence Protocol (PDCP) and Service Data Protocol (SDAP) for the NRRF interface to UEs 105, as defined in 3GPP TSs 38.331, 38.323, and37.324, respectively. An sNB-CU 307 may also be split into separatecontrol plane (sNB-CU-CP) and user plane (sNB-CU-UP) portions, where ansNB-CU-CP communicates with one or more AMFs 122 in one more 5GCNs 110using the NGAP protocol and where an sNB-CU-UP communicates with one ormore UPFs 130 in one more 5GCNs 110 using a General Packet Radio System(GPRS) tunneling protocol (GTP) user plane protocol (GTP-U) as definedin 3GPP TS 29.281. An sNB-DU 302 and sNB-CU 307 may communicate over anF1 interface to (a) support control plane signaling for a UE 105 usingInternet Protocol (IP), Stream Control Transmission Protocol (SCTP) andF1 Application Protocol (F1AP) protocols, and (b) to support user planedata transfer for a UE using IP, User Datagram Protocol (UDP), PDCP,SDAP, GTP-U and NR User Plane Protocol (NRUPP) protocols.

An sNB-CU 307 may communicate with one or more other sNB-CUs 307 and/orwith one more other gNBs 114 using terrestrial links to support an Xninterface between any pair of sNB-CUs 307 and/or between any sNB-CU 307and any gNB 114.

An sNB-DU 302 together with an sNB-CU 307 may: (i) support signalingconnections and voice and data bearers to UEs 105; (ii) support handoverof UEs 105 between different radio cells for the same sNB-DU 302 andbetween different sNB-DUs 302; and (iii) assist in the handover (ortransfer) of SVs 302 between different Earth stations 104, different5GCNs 110, and between different countries. An sNB-CU 307 may hide orobscure specific aspects of SVs 302 from a 5GCN 110, e.g. by interfacingto a 5GCN 110 in the same way or in a similar way to a gNB 114. ThesNB-CUs 307 may further assist in sharing of SVs 302 over multiplecountries.

In communication system 300, the sNB-DUs 302 that communicate with andare accessible from any sNB-CU 307 will change over time with LEO SVs302. With the split sNB architecture, a 5GCN 110 may connect to fixedsNB-CUs 307 which do not change over time and which may reducedifficulty with paging of a UE 105. For example, a 5GCN 110 may not needto know which SV/sNB-DUs 302 are needed for paging a UE 105. The networkarchitecture with regenerative SVs 302 with a split sNB architecture maythereby reduce 5GCN 119 impact at the expense of additional impact to ansNB-CU 307.

Support of regenerative SVs 302 with a split sNB architecture as shownin FIG. 3 may impact the communication system 300 as follows. The impactto 5GCN 110 may be limited as for transparent SVs 102 discussed above.For example, the 5GCN 110 may treat a satellite RAT in communicationsystem 300 as a new type of RAT with longer delay, reduced bandwidth andhigher error rate. Consequently, while there may be some impact to PDUsession establishment and Mobility Management (MM) and ConnectionManagement (CM) procedures, impacts to an AMF 122 (or LMF 124) may besmall—e.g. such as providing pre-configured data for fixed TAs and fixedcells to a UE 105 during Registration. The impact on SV/sNB-DUs 302 maybe less than the impact on SV/sNBs 202 (with non-split architecture), asdiscussed above in reference to FIG. 2. The SV/sNB-DU 302 may need tomanage changing association with different (fixed) sNB-CUs 307. Further,an SV/sNB-DU 302 may need to manage radio beams and radio cells. ThesNB-CU 307 impacts may be similar to sNB 106 impacts for a networkarchitecture with transparent SVs 102, as discussed above, except forextra impacts to manage changing associations with different sNB-DUs 302and reduced impacts to support radio cells and radio beams which may betransferred to sNB-DUs 302.

There are several SVOs currently operating and several additional SVOsthat are preparing to begin operations that may be capable of supportingsatellite access using 5G NR or some other wireless access type such asCDMA. Various SVOs may employ different numbers of LEO SVs and Earthgateways and may use different technologies. For example, currentlyoperating SVOs include SVOs using transparent (“bent pipe”) LEO SVs withCDMA, and regenerative LEO SVs capable of ISL. New SVOs have beenrecently announced with plans for large constellations of LEO SVs tosupport fixed Internet access. These various SDOs are widely known tothe industry.

While supporting satellite access to a wireless network, an SV102/202/302 may transmit radio beams (also referred to just as “beams”)over multiple countries. For example, a beam transmitted by an SV102/202/302 may overlap two or more countries. Sharing a beam over twoor more countries, however, may raise complications. For example, if abeam is shared by two or more countries, earth stations 104 and sNBs106/202/302/307 in one country may need to support UE 105 access fromother countries. Sharing a beam over multiple countries may raisesecurity issues for privacy of both data and voice. Further, sharing anSV beam over multiple countries may raise regulatory conflicts. Forexample, regulatory services including WEA, LI, and EM calls in a firstcountry may need support from sNBs 106/202/307 and earth stations 104 ina second country that shares the same SV beam.

A first solution to complications raised by beam sharing amongstmultiple countries may be to assign one beam to one country. Theassignment of a beam to a single country additionally implies assigningeach radio cell to one country. This solution may not preclude orprevent beam and radio cell coverage of additional countries, but canrestrict UE access to a beam and associated radio cell to just UEs 105in the country to which the beam and associated radio cell are assigned.A second solution for beam sharing over multiple countries could be toallow a 5GCN 110 in one country to support UEs 105 located in othercountries where regulatory approval for this was obtained from the othercountries. A third solution could be to share an sNB 106/202/307 among5GCNs 110 located in different countries (e.g. as in the case of sNB106-2, sNB 202-2 and sNB 307-2 shown in FIGS. 1-3), and to verify thateach UE 105 accessing the sNB 106/202/307 is registered in and connectedto a 5GCN 110 that is in the same country as the UE 105 or permitted toserve the country in which the UE 105 is located.

FIG. 4, by way of example, illustrates an SV 102, 202, 302 generatingmultiple beams identified as beams B1, B2, B3, B4, B5, and B6 over anarea 400 that includes portions of multiple countries, e.g., country A,country B, and country C. With the assignment of each beam to just onecountry as for the first solution above, beams B1, B3, B5 are assignedto country A, beams B4 and B6 are assigned to country B, and beam B2 isassigned to country C.

In one implementation, an individual beam may be assigned to a singlecountry by controlling or steering the beam. While a Non-GeostationaryEarth Orbiting (NGEO) SV has a moving coverage area, a relative beamdirection may be moved via a controllable antenna array to stay. ormostly stay, within one country, which is sometimes referred to as a“steerable beam”. For example, beam coverage may move slowly within onecountry and then hop to a new country, e.g., after an SV 102, 202, 302has transferred to a new earth station 104 or new sNB 106 or 307.

FIG. 5 illustrates radio cells produced by an SV 102, 202, 302 over anarea 500 that includes a number of Earth fixed cells 502. A radio cellmay comprise a single beam or multiple beams, e.g., all beams in a radiocell may use the same frequency or a radio cell may comprise one beamfor each frequency in a set of different frequencies. For example, beamsB1, B2 and B3 may support three separate radio cells (one beam per radiocell) or may collectively support a single radio cell (e.g., radio cell504 shown with dotted lines). Preferably, a radio cell covers acontiguous area.

Radio beams and radio cells produced by an SV 102, 202, 302 may notalign with cells used by terrestrial wireless networks, e.g., 5GCN 110terrestrial cells or LTE terrestrial cells. For example, in an urbanarea, a radio beam or radio cell produced by an SV 102, 202. 302 mayoverlap with many 5GCN terrestrial cells. When supporting satelliteaccess to a wireless network, radio beams and radio cells produced by anSV 102, 202, 302 may be hidden from a 5GCN 110.

As illustrated in FIG. 5, an area 500 may include a number of Earthfixed cells 502, as well as fixed tracking areas (TAs) such as TA 506.Fixed cells are not “real cells,” e.g., used for terrestrial NR and LTEaccess, and may be referred to as “virtual cells” or “geographic cells.”A fixed cell, such as fixed cells 502, has a fixed geographic coveragearea, which may be defined by a PLMN operator. For example, the coveragearea of a fixed cell or a fixed TA may comprise the interior of acircle, ellipse or a polygon. The coverage area is fixed relative to thesurface of the Earth and does not change with time, unlike the coveragearea of a radio cell which typically changes with time for a LEO or MEOSV. A fixed cell 502 may be treated by a 5GCN 110 the same as a cellthat supports terrestrial NR access. Groups of fixed cells 502 maydefine a fixed TA 506, which may be treated by a 5GCN the same as TAsthat are defined for terrestrial NR access. Fixed cells and fixed TAsused for 5G satellite wireless access may be used by a 5GCN 110 tosupport mobility management and regulatory services for UEs 105 withminimal new impact.

With regenerative SVs 202 with a non-split architecture as incommunication systems 200, each radio cell may remain with the same SV202 and may have a moving coverage area supporting different 5GCNs 110at different times.

With transparent SVs 102 and regenerative SVs 302 for a splitarchitecture as in communication system 300, each radio cell may beassigned to and controlled by one sNB 106 or 307 on behalf of one ormore PLMNs in one country. For a GEO SV 102/302, the assignment to ansNB 106/307 may be permanent or temporary. For example, the assignmentmay change on a daily basis to allow for peak traffic occurrence atdifferent times in different parts of the SV 102/302 radio footprintand/or may change over a longer period to accommodate changing regionaltraffic demands. For an NGEO SV 102/302, the assignment might last for ashort time, e.g., only 5-15 minutes. A non-permanent radio cell may thenbe transferred to a new sNB 106/307 as necessary (e.g. when access tothe NGEO SV 102/302 is transferred to the new sNB 106/307). Each sNB106/307, for example, may have a fixed geographic coverage area, e.g.,comprising a plurality of fixed cells 502 and fixed TAs. A radio cellfor a first NGEO SV 102/302 may be transferred from a first sNB 106/307to a second sNB 106/307 when (or after) moving into the fixed coveragearea of the second sNB 106/307. Prior to this transfer, UEs 105accessing the radio cell in a connected state may be moved to a newradio cell for the first sNB 106/307 or could be handed off to thesecond sNB 106/307 as part of transferring the radio cell. An SV 102/302may be accessed from only one sNB 106/307 or from multiple sNBs 106/307,possibly in different countries. In one implementation, an SV 102/302may be assigned to multiple sNBs 106/307 by partitioning radio cellsproduced by the SV 102/302 among the different sNBs 106/307. Radio cellsmay then be transferred to new sNBs 106/307 (and to new countries) asthe SV 102/302 moves or as traffic demands change. Such animplementation could be a form of a soft handoff in which SV 102/302transfer from one sNB 106/307 to another sNB 106/307 occurs inincrements of radio cells and not all at once.

FIG. 6 shows an example of assignment of radio cells, e.g., cell 1 andcell 2, produced by one or more SVs 102, 202, 302 over an area 600. Asillustrated, the area 600 includes a number of fixed TAs, e.g.,TA1-TA15, wherein TA4, TA5, TA8, and TA9 are assigned to an sNB1 (whichmay be an sNB 106, sNB 202 or an sNB 307), and TA12, TA13, TA14, andTA15 are assigned to an sNB2 (which may be another sNB 106, 202 or 307).In one implementation, a radio cell may be considered to support a fixedTA if the radio cell is wholly within the TA (e.g., Cell 2 within TA12); if the TA is wholly within the radio cell (e.g., TA4 within Cell1); or if the overlap of the area of a radio cell and a TA exceeds apredetermined threshold fraction of the total area of the radio cell orthe total area of the TA (e.g., cell 1 overlap with TA1, TA3, TA5, TA8or TA9). An SV 102, 202, 302 may broadcast, e.g., in a SystemInformation Block type 1 (SIB1) or SIB type 2 (SIB2), the identities(IDs) of supported PLMNs (e.g., where a PLMN ID comprises a MobileCountry Code (MCC) and Mobile Network Code (MNC)) and, for eachsupported PLMN, the IDs of supported TAs (e.g. where the ID of a TAcomprises a Tracking Area Code (TAC)). For an NGEO SV, the supportedPLMNs and TAs may change as radio cell coverage areas change. An sNB106/202/307 may determine PLMN and TA support (and thus the PLMN IDs andTACs which are broadcast in a SIB for each radio cell) from knownephemeris data for each SV 102/202/302 and a known directionality andangular range for component radio beams for each radio cell (e.g. Cell 1and Cell 2). An sNB 106/202/307 may then update SIB broadcasting.

Thus, as illustrated in FIG. 6, an SV 102/202/302 may broadcast for cell1 a SIB that includes TACs for TA4 and possibly TA1, TA3, TA5, TA8and/or TA9. Similarly, the SV 102/202/302 or another SV 102/202/302 maybroadcast for Cell 2 a SIB that includes a TAC for TA12 only. The Cell 1may be assigned to sNB1 (which has coverage of TA4, TA5, TA8, and TA9)and Cell 2 may be assigned to sNB2 (which has coverage of TA12, TA13,TA14, and TA15). Cell 1 and Cell 2 may be transferred from sNB1 to sNB2or from sNB2 to sNB1 if the cell coverage area moves from one sNB areato another.

The coverage area for a fixed TA may be defined in a manner that issimple, precise, flexible and requires minimal signaling for conveyanceto a UE 105 or sNB 106/202/307. A fixed TA area may be small enough toallow efficient paging by comprising an area supported by just a fewradio cells (e.g. less than 20) and may also be large enough to avoidexcessive UE registration (e.g. may extend at least several kilometersin any direction). The shape of a fixed TA area may be arbitrary, e.g.,the shape may be defined by a PLMN operator, or may have one or morerestrictions. For example, one restriction for the shape of the fixed TAarea may be that a fixed TA along the border of a country preciselyaligns with the border to avoid serving UEs 105 in another country.Additionally, a fixed TA may be restricted to align with an area ofinterest, e.g., a PSAP serving area, the area of a large campus, etc.Additionally, a fixed TA may be restricted so that parts of the fixed TAalign with a physical obstacle, such as the bank of a river or lake.

The coverage area for fixed cells may likewise be defined in a mannerthat is simple, precise, flexible and requires minimal signaling forconveyance to a UE 105 or sNB 106/202/307. A fixed cell coverage areamay allow for simple and precise association with a fixed TA, e.g., onefixed cell may belong unambiguously to one TA.

Fixed cells may be used by a wireless core network, such as a 5GCN 110,for support of regulatory services such as emergency (EM) call routingbased on a current fixed serving cell for a UE 105, use of a fixed cellto approximate a UE 105 location, use of a fixed cell association todirect a Wireless Emergency Alerting (WEA) alert over a small definedarea to a recipient UE 105, or use of a fixed cell as an approximatelocation or a trigger event for Lawful Interception (LI) for a UE 105.Such usage of fixed cells implies that fixed cells should be capable ofbeing defined with a size and shape similar to that of cells that aredefined and used for terrestrial wireless access, including allowing forvery small (e.g., pico) cells and large (e.g., rural) cells.

Aspects of SOLUTION 1 are next discussed with reference to FIGS. 7 to22. In some of these aspects, fixed cells and fixed TAs may be definedusing grid points, but the definition of the fixed cells and fixed TAsmay be independent and not require that each fixed cell belong to onlyone TA.

FIG. 7 is a diagram illustrating a geographic area 700 that includes anumber of fixed cells 702 defined by a plurality of cell center gridpoints 704, and further includes a plurality of fixed TAs 706-1, 706-2,706-3, and 706-4, and fine grid points 708. As illustrated, the cellcenters for the fixed cells 702 are defined by a rectangular coarsearray of grid points 704. The shape and area of each fixed cell arebased on the following definition, referred to as “Definition A”: eachfixed cell area includes all locations that are closer to the cellcenter grid point than to any other cell center grid point. With thisdefinition, the resulting fixed cell areas are rectangular as shown inFIG. 7 with the cell center grid point for each fixed cell being locatedat the center of the fixed cell area. FIG. 7 includes a non-rectangularregular fixed TA 706-1 and a rectangular regular fixed TA 706-2. Aregular fixed TA includes only complete fixed cell areas. FIG. 7 alsoincludes irregular fixed TAs 706-3 and 706-4. Irregular fixed TAsinclude fractions of fixed cell areas. A fixed TA area may be defined byeither the coarse grid points 704 or the fine grid points 708 that areincluded in the fixed TA area. For example, the fine grid points 708 mayhave, e.g. 10-50 meters grid point spacing which may allow a moreprecise definition of a TA area (e.g. for an irregular fixed TA). Theirregular fixed TAs may be used when a precise TA boundary is needed,e.g., between two countries.

FIG. 8 is a diagram illustrating a geographic area 800 that includes anumber of hexagonal fixed cells 802 defined by a plurality of cellcenter grid points 804, and further includes a plurality of fixed TAs806-1, 806-2, and 806-3, and fine grid points 808. As illustrated, thecell center grid points 804 for the fixed cells 802 are defined by rowsand columns that are alternately offset from one another by half of theinter-cell center distance. The resulting cell areas, according to theprevious Definition A, are then hexagonal rather than rectangular. Theuse of hexagonal fixed cells 802, rather than rectangular cells as inFIG. 7, may provide a closer approximation to real terrestrial cellareas, which may be useful, e.g., to enable more accurate cell ID basedlocation or more controlled WEA Alert broadcasting. FIG. 8 includesregular fixed TAs 806-1 and 806-2 and an irregular fixed TA 806-3. Theregular fixed TAs 806-1 and 806-2 include only complete (hexagonal)fixed cell areas. The irregular fixed TA 806-3 includes fractions and/orextensions of hexagonal fixed cell areas. An irregular fixed TA area maybe defined by specifying included fine grid points and included wholefixed cells.

Cell center grid points, such as cell center grid points 704 and 804 inFIGS. 7 and 8, may be defined via X and Y spacing and a referencelatitude and longitude. FIG. 9, by way of example, illustrates a numberof cell center grid points 904 for rectangular cells and one rectangularfixed cell 902. The cell center grid points 904 may be defined based onan X spacing and a Y spacing, where the X and Y directions areorthogonal and may be aligned with a line of latitude (East-West) and aline of longitude (North-South), respectively. The spacing may then bedefined in units of arc seconds (e.g. units of 0.1 arc sec which equalsaround 3 meters). A reference latitude and longitude may be provided forone “reference cell center” grid point, e.g., grid point 904 _(ref),which may be at an extreme North East, North West, South East or SouthWest corner (e.g. a South West corner in the example in FIG. 9) of thecell center array.

FIG. 10 illustrates a number of cell center grid points 1004 defininghexagonal fixed cells and one example hexagonal fixed cell 1002. Thecell center grid points 1004 may be in a hexagonal array, e.g., withrows (or columns) offset by half a spacing unit as illustrated in FIG.10, and may be defined based on an X spacing and a Y spacing, as well asa latitude and longitude for a reference cell center grid point 1004_(ref). Additionally, the orientation (East-West vs North-South) of theX (or Y) spacing may be defined.

In some implementations, a Z spacing, e.g., vertical spacing, may alsobe defined to in order to define 3D fixed cells. For example, the lowestcell center grid points may be at the local ground level. Higher cellcenter grid points may then be used to define fixed cells above groundlevel and to provide separate cell IDs that may be used for aerialvehicles, such as drones.

Fine grid points may be defined as the same manner as cell center gridpoints 904 or 1004, but with a smaller X spacing and/or Y spacing. Finegrid points may be arranged in a rectangular array, e.g., as illustratedin FIG. 9, but in some implementations may be arranged in a hexagonalarray, as illustrated in FIG. 10.

In some implementations, grid points, such as cell center grid points904 and 1004, or fine grid points may be restricted to aligning a subsetof grid points with lines of latitude and longitude for either integer(non-fractional) degrees or integer degrees plus integer minutes, e.g.,to simplify the definition of the grid points. The X and Y spacing arethen each defined as an exact divisor of one degree or one minute. Forexample, if X spacing and Y spacing are defined in units of 0.1″ (0.1seconds), an X spacing or Y spacing may be assigned a value of N units,where N exactly divides 600 (one minute) or 36000 (one degree). Byaligning a subset of grid points with lines of latitude and longitude,all the grid points may be defined using a single parameter to definethe spacing plus one Boolean parameters to define whether the alignmentis to degrees or to minutes. For example, with a value of N=2000 and analignment with degrees, a subset of grid points would have a latitudeand longitude of the form (x, y), where x and y both comprise an integernumber of degrees, with remaining grid points successively spaced at Xand Y intervals of 200″ between these.

FIG. 11 is a diagram illustrating a geographic area 1100 with a numberof fixed cells 1102 defined by a plurality of rectangular grid points1104. FIG. 11, further illustrates a regular fixed TA 1106 with boldlines. As illustrated in FIG. 11, grid points 1104 may be defined inrows and columns and may be specified, e.g., by latitude and longitude,as described previously. Each grid point 1104 defines a fixed cell 1102.Based on the Definition A above, the area of a fixed cell 1102associated with a grid point G may be defined as including any locationL that is closer to grid point G than to any other grid point. Asillustrated, the resulting fixed cells 1102 in FIG. 11 are rectangularor square. In one implementation, a regular fixed TA may be definedbased on the fixed cells 1102. A regular TA includes only complete fixedcell areas, i.e., the border of a regular fixed TA will coincide withthe borders of one or more fixed cells. As illustrated in FIG. 11, aregular fixed TA may be defined based on an X cell center count and a Ycell center count and a latitude and longitude of one cell center todefine a square or rectangular fixed TA. For example, the regular fixedTA 1106 may be defined based on the X cell center count (i.e., count 3)and the Y cell center count (i.e., count 2) and the latitude andlongitude of grid point 1104 _(TA).

FIG. 12 is a diagram illustrating a geographic area 1200 with a numberof fixed cells 1202 defined by a plurality of grid points 1204 and aregular fixed TA 1206 with bold lines. As described in FIGS. 7, 9 and11, the grid points 1204 may be defined in rows and columns, e.g.,specified by latitude and longitude, where each grid point 1204 definesa square or rectangular fixed cell 1202. A non-rectangular, regularfixed TA may be defined based on the fixed cells 1202 that it containsby defining row (or column) cell center counts and offsets and thelatitude and longitude of one cell center. For example, as illustratedin FIG. 12, the fixed TA 1206 may be defined based on the latitude andlongitude of grid point 1204 _(TA), a cell center count in a first row1206 ₁ (i.e., count 5), an offset and cell center count in a second row1206 ₂ (i.e., offset+1, count 4), and an offset and cell center count ina third row 1206 ₃ (i.e., offset+2, count 2).

FIG. 13 is a diagram illustrating a geographic area 1300 with a numberof fixed cells 1302 defined by a plurality of hexagonal grid points 1304and a regular fixed TA 1306 with bold lines. As described in FIGS. 8 and10, the grid points 1304 may be defined in rows and columns, e.g.,specified by latitude and longitude, in a hexagonal array so that eachgrid point 1304 defines a hexagonal fixed cell 1302. A regular fixed TAmay be defined based on the fixed cells 1302 by defining the fixed TAbased on a X cell center count and a Y cell center count and a latitudeand longitude of one cell center with a convention that hexagonaloffsets include an extra half grid spacing in an East direction for rowsor North direction for columns. For example, the regular fixed TA 1306may be defined based on the X cell center count (i.e., count 3) and theY cell center count (i.e., count 2) and the latitude and longitude ofgrid point 1304 _(TA), with the convention that alternate rows areoffset by one half grid spacing in an East direction.

FIG. 14 is a diagram illustrating a geographic area 1400 with a numberof hexagonal fixed cells 1402 defined by a plurality of grid points 1404and a regular fixed TA 1406 with bold lines. As described in FIGS. 8 and10, the grid points 1404 may be defined in rows and columns, e.g.,specified by latitude and longitude, in a hexagonal array so that eachgrid point 1404 defines a hexagonal fixed cell 1402. A regular fixed TAmay be defined based on the fixed cells 1402 by defining row (or column)cell center counts and offsets and the latitude and longitude of onecell center with a convention that hexagonal offsets include an extrahalf grid spacing in an East direction for rows or North direction forcolumns. For example, as illustrated in FIG. 14, the fixed TA 1406 maybe defined based the latitude and longitude of grid point 1404 _(TA), acell center count in a first row 1406 _(Row1) (i.e., count 4), an offsetand cell center count in a second row 1406 _(Row2) (i.e., offset +1,count 4), and an offset and cell center count in a third row 1406_(Row3) (i.e., offset −1, count 5), with the convention that each offsetincludes an additional half grid spacing in the East direction.

In the case of a regular fixed TA having one or more rows (or columns)in which cell centers are missing, e.g., non-consecutive fixed cells ina row are in the fixed TA, counts may be provided of alternate includedand non-included cell centers. In addition, or as an alternative, a bitmap may be used to define a regular fixed TA. For example, a bit map fora fixed TA may be provided that defines the fixed TA based on includecell centers (bit=1) and non-included cell centers (bit=0).

In addition to regular fixed TAs, irregular fixed TAs may also be used.An irregular fixed TA is not limited to complete fixed cell areas andmay include fractions of fixed cell areas. An irregular fixed TA may beused, for example, where a precise TA boundary is needed, e.g., between2 countries. An irregular fixed TA may be defined using an array ofadditional grid points, sometimes referred to herein as a fine gridpoint array. An irregular fixed TA may still be related to fixed cellsin terms of defining or configuring which fixed cells are completelyincluded in a fixed TA and which fixed cells are only partially includedthe fixed TA.

FIG. 15, for example, is a diagram illustrating a geographic area 1500with a number of fixed cells 1502 defined by a plurality of center cellgrid points 1504. Additionally, the geographic area 1500 includes finegrid points 1508 in an array. The fine grid points, for example, have asmaller grid point spacing than the center cell grid points 1504. Thegeographic area 1500 includes an irregular fixed TA 1506, illustratedwith bold lines, that is defined by the fine grid point array. Asillustrated, the irregular fixed TA 1506 may include fractions of fixedcells 1502. Similar to regular fixed TAs, an irregular fixed TA may bedefined using row (or column) grid point counts and offsets, along witha latitude and longitude of one grid point. With irregular fixed TAs,however, fine grid points 1508 may be used to define the fixed TAinstead of cell center grid points 1504 as used with regular fixed TAs.FIG. 15, for example, illustrates the irregular fixed TA 1506 as beingdefined based on the latitude and longitude of fine grid point 1508_(TA), and for each row of fine grid points, an offset (for rows otherthan the first row) and either a fine grid point count or a bit maprepresentation, where bit=1 to indicate the inclusion of a fine gridpoint and bit=0 to indicate exclusion of a fine grid point.

As illustrated, the perimeter of the irregular fixed TA 1506 may extendout by one half of a fine grid point spacing from the outermost definedgrid points. The cell center grid points 1504 that are on the perimeterof or within the TA area are defined as belonging to the irregular fixedTA 1506. In some implementations, an irregular fixed TA may be definedas the union of a regular fixed TA (defined via cell centers) andsmaller irregular fixed TAs (defined by fine grid points) to reduce datasize. In another alternative, an irregular fixed TA may be defined as apolygon (sequence of straight line segments) by defining the vertices ofthe TA, e.g., using the latitude and longitude of fine grid points 1508.

FIG. 16 is a diagram illustrating a geographic area 1600 with a numberof fixed cells 1602 defined by a plurality of center cell grid points1604 and with an irregular fixed TA 1606, illustrated with bold lines.FIG. 16 illustrates a technique for assigning identities to fixed cellswith a reduced amount of signaling. The fixed cells in FIG. 16 are eachlabelled (as C1, C2, C3 etc.) for the purpose of illustration, thoughthese labels do not form part of the cell identities being assigned. Ina first step, the fixed cells included in a fixed TA are implicitlyordered according to some known or defined convention. In a second step,identities are assigned to the fixed cells based on their implicitordering. For the first step, FIG. 16 shows two examples of cellordering (row wise ordering and alternate row wise ordering), as shownby the two alternative orderings of the cell labels in FIG. 16, butother orderings are also possible. For the second step, cell identitiesmay be assigned consecutively, for example, as:

Cell ID=TA Base Value+Cell sequence number

where the TA Base Value is an initial cell identity for the first cellin the TA allows and the Cell sequence number is the position of eachcell in the cell ordering (0, 1, 2, 3 etc.). Alternatively, cell IDs maybe individually specified via a sequence c1, c2, c3, c4 etc., where thecell ID ci is assigned to each cell with sequence number i.

For an irregular fixed TA, e.g., as illustrated in FIG. 16, cells insidethe fixed that are adjacent to the fixed TA border (e.g. cells C1, C2,C3, C4, C5, C6, C8, C9, C11, C12, C13, C14, C15, C16, C17, C18, C19 inFIG. 16) may be flagged to assist in the determination of whether UE isinside or outside the fixed TA. The flags, for example, may be providedas a bit map based on the cell ordering. For a UE known to be insidesuch a flagged cell, more precise location of the UE may be used todetermine whether the UE is actually inside the TA, as described belowin association with FIG. 18.

FIG. 17 shows a number of cell center grid points 1702-1, 1702-2,1702-3, and 1702-4 and a UE 105 and illustrates fixed serving cell andTA determination for a regular TA. As illustrated, the UE 105 is adistance D1 from grid point 1702-1, a distance D2 from grid point1702-2, a distance D3 from grid point 1702-3, and a distance D4 fromgrid point 1702-4. The serving cell center grid point may be defined tobe the cell center grid point closest to the UE 105. As illustrated inFIG. 17, D3 is less than D1, D2, or D4, and accordingly, grid point1702-3 is the serving cell center grid point. Typically, the location ofUE 105 would be determined (e.g. by UE 105 using GNSS measurements) andthen the distances to nearby cell center grid points are determined(e.g. by UE 105) based on known locations for the cell center gridpoints. Based on the fixed serving cell, the associated regular fixed TAmay then be determined (e.g. by UE 105) based on the TA which includethe fixed serving cell.

FIG. 18 shows a number of fine grid points 1808 and an irregular fixedTA 1806, and two UEs 105-1 and 105-2, and illustrates determination ofan irregular fixed TA. Here, the UE 105 or network may first determinethe closest cell center grid point within the irregular fixed TA asdescribed for FIG. 17. If the closest cell center grid point indicatesproximity to the TA boundary, e.g., boundary 1807, the UE 105 or networkmay determine whether the UE 105 is inside or outside the fixed TA fromeither the closest fine grid point when fine grid points are defined orwhether the UE 105 is inside or outside a polygon definition for a fixedTA. For example, as illustrated in FIG. 18, the UE 105-1 is inside thefixed TA 1806 as the closest fine grid point G1 belongs to the fixed TA1806. The UE 105-2, however, is outside the fixed TA 1806 as the closestfine grid point G7 does not belong to the fixed TA 1806.

Information descriptive of fixed cells and fixed TAs may be transferredto a UE 105 (or sNB 106/202/307) in a compressed form to reducesignaling. To reduce later processing, the information may be expanded,after being received by a UE 105 (or sNB 106/202/307) into a tableindexed by cell center X and Y coordinate indices. FIG. 19 illustratesan example of a table 1900 that is indexed by a cell center X coordinateindex and a cell center Y coordinate index. A reference cell center(e.g., 1104 _(TA), 1204 _(TA), 1304 _(TA), or 1404 _(TA)) is used forthe origin (<0,0> where X=0 and Y=0) and subsequent cell centers eitherEast or West and either South or North of this receive increasing X andY indices. Stored information for each cell (having particular a pair ofcell center X and Y indices) may include either a “not applicable”indication if the cell is not part of any TA or a Cell ID, Tracking AreaIdentifier (TAI) and an indication for an irregular TA as to whether thecell is adjacent to a TA border. To determine a serving cell for a UE105, a location for the UE 105 may first be obtained and then convertedto X and Y coordinate indices by determining the closed X coordinate andclosest Y coordinate based on known location coordinates for the arrayof cell centers (e.g. as further described below for FIG. 20). Servingcell information for the UE 105 including serving cell ID and TA maythen be obtained by a simple table lookup.

FIG. 20 shows a number of grid points 2002, which may be cell centers orfine grid points and a UE 105 and illustrates one implementation of thedetermination of a closest (e.g. serving) cell center or fine gridpoint. The location of the UE 105 may be determined (e.g. using GNSS) interms of latitude and longitude, which may be converted into cellcoordinate indices by subtracting a latitude and longitude,respectively, for a reference cell center 2004 _(ref) and then dividingby a Y (latitude) and X (longitude) spacing, respectively. For example,an X cell coordinate index 2012 may be determined as:

$\begin{matrix}{{{X\mspace{14mu}{cell}\mspace{14mu}{coordinate}\mspace{14mu}{index}} = \lfloor \frac{{UE}\mspace{14mu}{Longitude}\text{-}{Reference}\mspace{14mu}{Longitude}}{X\mspace{14mu}{Spacing}} \rfloor},} & {{Eq}.\mspace{14mu} 1}\end{matrix}$

and a Y cell coordinate index 2014 may be determined as:

$\begin{matrix}{{{Y\mspace{14mu}{cell}\mspace{14mu}{coordinate}\mspace{14mu}{index}} = \lfloor \frac{{UE}\mspace{14mu}{Latitude}\text{-}{Reference}\mspace{14mu}{Latitude}}{Y\mspace{14mu}{Spacing}} \rfloor},} & {{Eq}.\mspace{14mu} 2}\end{matrix}$

The X and Y cell coordinate indices define a nearby cell center gridpoint, e.g., grid point 2004 _(near), which may or may not be theclosest grid point to the UE 102. The X and Y coordinate offsets for theUE 102 from this nearby cell center grid point 2004 _(near) may also beobtained via modulo operations. For example, the X cell center offset2016 may be determined as:

X cell center offset=(UE Longitude−Reference Longitude)mod Xspacing,  Eq. 3

and the Y cell center offset 2018 may be determined as:

Y cell center offset=(UE Latitude−Reference Latitude)mod Y spacing,  Eq.4

The determined X and Y offsets may be used to determine the coordinateindices of the closest cell center grid point 2004 _(closest), which isthe cell center for the fixed cell 2002 within which the UE 102 islocated. For example, if the determined X offset is greater than halfthe X spacing, the X cell coordinate index is increased by one andsimilarly, if the determined Y offset is greater than half the Yspacing, the Y cell coordinate index is increased by one, to define theclosest cell center grid point 2004 _(closest).

For hexagonal fixed cells, alternate shifting of cell centers by onehalf the spacing needs to be take into account for the offsetcalculation. A UE 105 or sNB 106/202/307 may perform a simple tablelookup to obtain the cell related information, e.g., using a tablesimilar to that shown in FIG. 19. Determination of a closest fine gridpoints employ the same techniques as in FIG. 20 but using the fine gridpoint spacings and reference latitude and longitude.

The previous definitions, techniques and their examples in which fixedTAs and fixed cells are associated with one another by requiring (orassuming) that each fixed cell belongs to only one fixed TA, similar toterrestrial cells and TAs, may lead to some complexity in defining fixedcells and fixed TAs and identifying a fixed serving cell and associatedfixed TA for a UE 105 with satellite access.

Accordingly, in some implementations, fixed TAs and fixed cells aredefined independently of one another, which may provide a simplifiedsolution. In one implementation, the cell identifier for each fixed cellmay be defined using latitude and longitude coordinates of a UE 105.Thus, a serving cell ID for a UE 105 (e.g., in a non-access stratum(NAS) message or a session initiation protocol (SIP) message) isreplaced by the location of the UE 105 (e.g., latitude and longitudecoordinates (lat/long)). This means that fixed cells are no longerpre-defined but are represented by locations. The use of a UE 105lat/long in place of a cell ID will impact 5GCN 110 features that makeuse of a serving cell ID (e.g., for routing of an EM call or broadcastof a WEA alert).

In another implementation, referred to as implementation I1, the cellidentifier for each fixed cell may be defined by coarsened latitude andlongitude coordinates of the UE 105, e.g., pseudo lat/long. For example,the UE 105 latitude and longitude may be expressed as signed binaryfractions (e.g. of 90° for latitude or 180 for longitude) and coarsenedby either truncating less significant binary digits or rounding lesssignificant binary digits in order to fit into a predetermined number ofbits, e.g., 36 bits. The coarsened lat/long may be unique both within aPLMN and worldwide, and accordingly, may be used as a fixed cell ID. Theuse of a coarsened lat/long as a fixed cell ID could enable fixed cellIDs to be retained and treated either as cell IDs or as coarse UElocations. If the coarsened lat/long is to remain unique worldwide, theprecision of each of the latitude and longitude coordinates (aftercoarsening) may be around 75 meters, e.g., for latitude and longitudeeach expressed using 18 bits, which would mean a minimum UE locationerror (when a cell ID is used as a location) of around 100 meters.However, with lat/long restricted to a smaller geographic region,location error may be reduced by a factor of 2 or 4 or more, e.g., toaround 25 meters for the US.

Cell IDs defined by coarsened latitude and longitude coordinates, asjust described, would define locations of a rectangular array of gridpoints (e.g. as shown in FIG. 11). When rounding of location coordinatesis used to fit into a predetermined number of bits, which may beequivalent to applying Definition A described previously, cell areaswould be rectangular with the location of each cell ID being at thecenter of the associated cell area. With truncation of locationcoordinates to fit into a predetermined number of bits, cell areas wouldalso be rectangular but with the location of each cell ID being at onecorner of the associated cell area.

In another implementation, referred to herein as implementation I2,fixed cells may be defined using a rectangular or hexagonal grid pointarray of cell centers as described in FIGS. 7-19. For example, each gridpoint in an array of grid points may define one fixed cell and has oneassociated cell identifier. Definition A described previously may beused, whereby a fixed cell includes a coverage area of locations thatare closer to a location of the grid point for that fixed cell than to alocation of any other grid point in the array of grid points. Two ormore alternative arrays may be defined with different grid pointspacings to define fixed cells of different sizes, e.g., closer spacedgrid points may be used for small fixed cells for urban and suburbanareas and wider spaced grid points may be used for larger fixed cellsfor rural and other sparsely populated areas.

In implementation 2, fixed TAs may be defined using a fine grid pointarray, e.g., as described in FIGS. 7, 8, 9, 10, 15 and 20. Thedefinition of each fixed TA may be based on fine grid points and may notmake use of fixed cells or an array fixed cell centers. Alternatively,in implementation 2, a fixed TA may be defined as a polygon (e.g., bydefining the lat/long for a sequence of vertices of the fixed TA) or assome other geometric shape such as circle or ellipse. In implementationI2, fixed TAs may also be defined using a mixture of different shapes.

In implementation 2, the definitions of fixed cells and fixed TAs areallowed to be independent of one another. A consequence is that a fixedcell may not wholly lie inside just one fixed TA but may overlap withtwo or more TAs. This independence may make definition simpler. Forexample, if a fixed TA is defined as an irregular polygon, attempting todefine a large number of fixed cells that must all be wholly includedwithin the TA could be complex. But if fixed cells are definedseparately from fixed TAs, the complexity disappears. Although thismeans that some fixed cells may not each be part of just one fixed TA,this may not matter since global cell IDs may not contain a TA identity(TAI) and may thus not be required to identify a unique TA. Instead,fixed cell IDs and TAIs may be used for their respective purposeswithout mutual conflict (e.g. to support paging and mobility in the caseof TAIs and regulatory services and approximate location of a UE 105 inthe case of fixed cell IDs).

However, if it is preferred to define and identify fixed cells which areeach wholly within a single fixed TA, the independent definition offixed cells and fixed TAs as just described for Implementation I2 may beextended. This may be done by defining fixed cell IDs as having twocomponents—a base ID corresponding to an initial independent definitionof a “base cell” (e.g. a rectangle or hexagon for a regular array ofgrid points) and a color code which is appended to the base ID andcorresponds to a fixed TA within which a portion of the base cell isincluded.

FIGS. 21A and 21B provide an illustration of Implementation I2 in whichTA color codes are used to define unique cell portions and unique cellIDs. Unless specified otherwise, FIGS. 21A and 21B may be jointlyreferred to as FIG. 21.

FIG. 21B illustrates a geographic region 2150 that includes arectangular base cell 2152 that overlaps with three separate fixed TAs2156-1, 2156-2 and 2156-3 (collectively referred to as TAs 2156). By wayof example, the three TAs 2156 may be color coded with three colorsusing 2 bits, e.g., TA 2156-1 is coded binary 01 (green), TA 2156-2 iscoded binary 10 (yellow), and TA 2106-3 is coded binary 11 (red). Thebase cell 2152 is split into three separate cell portions 2152-1,2152-2, and 2152-3, which may each be assigned a unique cell ID byadding (e.g. appending or prepending) the color code of each TA to an IDfor the base cell 2152. To illustrate this for FIG. 21B, assume that thebase cell 2152 has an ID cccccc, where cccccc represents a bit stringwith (for example) 34 bits. Cell portion 2152-1 can then have a cell IDcccccc01, cell portion 2152-2 can have a cell ID cccccc10, and cellportion 2152-3 can have a cell ID cccccc11. These new cells IDs are alldistinct and have (in this example) 36 bits which can happen to be thesize of a cell ID defined for 5G NR.

In a more general case, the serving cell ID for any UE 105 could bedetermined from both a base cell in which the UE 105 is located (e.g.the rectangular cell 2152 in FIG. 21B) and the TA in which the UE 105 islocated (e.g. TA 2156-1, 2156-2, or 2156-3 in FIG. 21B). The color codescould enable a unique cell ID for the UE 105 as long as no two fixed TAsthat share part of the same boundary or the same vertex have the samecolor code and as long as base cells are small enough to overlap with nomore than one common vertex for the fixed TAs.

With a further (optional) restriction that no more than three fixed TAsshare a common vertex (which means in general that the three fixed TAswill also share part of a common boundary), then the requirement ofhaving different color codes becomes equivalent to coloring a map withno two adjacent countries sharing the same color. This corresponds tothe well known Four Color Theorem, which states that four colors areenough. Hence, with these restrictions, four TA color codes (requiringjust 2 bits) could be enough to generate unique cell IDs, which is areason for using the term “color code”.) In this case, base cell IDs maycomprise 34 bits as in the example for FIG. 21B—leading to normal 36 bitcell IDs as used for 5G NR when extended with the 2 bit color code.

As an example of implementation I2, basic fixed cell IDs may be defined(independently of TAs) using 34 bits, which are used whenever a fixedserving TA does not need to be known. For example, the 34 bit cell IDsmay be used to approximate a location of a UE 105 based on a locationfor a fixed serving cell, or to route an EM call to a PSAP associatedwith a serving cell ID. A 2 bit color code associated with a fixed TA inwhich a UE 105 is located may be appended to a basic fixed cell ID for aserving cell for the UE 105, resulting in a 36 bit ID for the portion ofthe fixed serving cell that is located inside the fixed TA. The 36 bitfixed cell ID may be used for signaling (e.g., included in RadioResource Control (RRC) and NGAP messages) and may be used to determine afixed TA for the UE 105 and/or to identify the serving cell portion forthe UE 105 that is inside the fixed TA.

FIG. 21A provides another illustration of a geographic area 2100 thatincludes a number of fixed cells 2102 and a number of fixed TAs 2106-1,2106-2, 2106-3, and 2106-4 (collectively referred to as fixed TAs 2106),which are defined independently of each other. The fixed cells 2102, forexample, may be defined based on a plurality of cell center grid points2104, or based on other techniques, such as defining a cell identifierbased on coarsened location coordinates of the UE 105. As illustrated inFIG. 21A, the cell centers 2104 may be defined by rows and columns thatare alternately offset from one another by half of the inter-cell centerdistance, resulting in hexagonal fixed cells 2102.

The boundaries of the fixed TAs 2106 (shown by the bold lines) aredefined independently from the fixed cells 2102 and only partially alignwith fixed cell boundaries. For example, the fixed TAs 2106 may bedefined based on an array of fine grid points (such as that illustratedin FIG. 15) or based on a sequence of vertices of the fixed TAs 2106.The fixed TAs are color coded with four colors using two bits. Asillustrated, some fixed cells 2102 overlap with two or three fixed TAs2106, such as fixed cells c2, c3, and c4.

Each fixed TA 2106 may be assigned a distinct 24 bit tracking area code(TAC) and a 2 bit color code. Each fixed cell 2102 may be assigned adistinct 34 bit cell identity, e.g., which may include an sNB identity.A 36 bit unique cell identity (ID) may be obtained by combining the 34bit fixed cell ID with the 2 bit fixed TA color code. Combining thefixed cell ID and the fixed TA color code results in two or more uniquecell IDs for fixed cells 2102 that overlap two or more fixed TAs, whichmay be treated as identifying separate fixed cells. A 2 bit color codemay suffice provided only 3 fixed TAs share a common vertex, e.g. as atlocation L7. When 4 or more fixed TAs share a common vertex, a 3 (or 4)bit color code may be used.

Byway of example, the fixed TAs 2106 in FIG. 21B may be color coded withfour colors using 2 bits, e.g., fixed TA 2106-1 is 00 (blue), fixed TA2106-2 is 01 (green), fixed TA 2106-3 is 10 (yellow), and fixed TA2106-4 is 11 (red). The fixed cells 2102 may be each assigned a 34 bitcell identity (cid), e.g., fixed cell c1 is assigned <cid1>, fixed cellc2 is assigned <cid2>, fixed cell c3 is assigned <cid3>, and fixed cellc4 is assigned <cid4>, where each of <cid1>, <cid2>, <cid3> and <cid4>represents a sequence of 34 bits. By combining a 34 bit fixed cellidentity with a 2 bit color code for a fixed TA, the following 36 bitunique cell IDs are generated for a UE 105 at different locations indifferent fixed cells as indicated in Table 1.

TABLE 1 UE 105 Location and Cell 36 Bit Unique Cell ID Any Location inCell c1 <cid1>01 Location L1 in Cell c2 <cid2>01 Location L2 in Cell c2<cid2>10 Location L3 in Cell c3 <cid3>01 Location L4 in Cell c3 <cid3>11Location L5 in Cell c4 <cid4>00 Location L6 in Cell c4 <cid4>11

FIG. 22 shows a signaling flow 2200 that illustrates use of fixed TAsand fixed cells to support network access by, and services for, a UE 105according to the implementations described above, includingImplementation I1 and Implementation I2. FIG. 22 shows various messagessent between components of a communication network, such ascommunication networks 100, 200, and 300 depicted in FIGS. 1, 2, and 3,respectively FIG. 22 illustrates a procedure for a UE 105 to access aserving PLMN through SVs 102/202/302 and sNBs 106/202/307. The sNBs106/202/307 are illustrated as separate from the SVs 102/202/302 forclarity, but it should be understood that an sNB 106/202/307, or aportion of an sNB 106/202/307, may be included within an SV 102/202/302.For example, an sNB 202 would typically be part of an SV 202, and an sNB307 (or sNB-CU 307) would typically be in communication with one or moresNB-DUs 302 that are part of SVs 302.

At stage 1 in FIG. 22, configuration data is transmitted from an AMF 122to a UE 105 via an sNB 106/202/307 and an SV 102/202/302, e.g., usingbroadcast or unicast. For example, in the case of the unicast, UE 105may send a NAS Registration Request message to AMF 122, and AMF 122 mayreturn a NAS Registration Accept message to UE 105 which includes theconfiguration data. The configuration data includes, for example,configuration information related to fixed cells and/or fixed TAs in thewireless coverage of the SV 102/202/302 and that is associated with aserving PLMN for UE 105. As discussed above, for example, the fixedcells and/or fixed TAs may be defined as fixed geographic areas and maybe defined independently of each other. Each fixed cell is assigned acell identifier and each fixed TA is assigned a tracking area code (TAC)and an optional color code, where adjacent fixed TAs are assigneddifferent color codes. The configuration information for the fixed cellsmay include locations of grid points in an array of grid points and cellidentifiers associated with the array of grid points, e.g., where eachgrid point defines a fixed cell and has one associated cell identifier.A fixed cell includes a coverage area of locations that are closer tothe grid point for that fixed cell than to any other grid point.Similarly, the configuration information for the fixed TAs may includelocations of grid points in an array of grid points and tracking areacodes and color codes associated with the array of grid points, e.g.,where each grid point defines a fixed TA and has one associated TA codeand one optional associated color code. A fixed TA may include acoverage area of locations that are closer to a location of the gridpoint for that fixed TA than to any other grid point. Alternatively, theconfiguration information for a fixed TA may include locations ofvertices for a plurality of polygons and tracking area codes andoptional color codes associated with the plurality of polygons. Eachpolygon in the plurality of polygons may define a fixed TA and has anassociated TA code and optional associated color code, and the fixed TAincludes a coverage area of locations contained within the polygon.

At stage 2, the UE 105 may receive DL signals from one more SVs102/202/302.

At stage 3, the UE 105 may obtain location measurements from the DLsignals from SVs 102/202/302 from stage 2. The UE 105 may additionallyor alternatively obtain location measurements from DL signals receivedfrom GNSS SVs 190 and/or terrestrial base stations (BSs) such as gNB114.

At stage 4, the UE 105 may obtain its position based on the locationmeasurements. The UE 105, for example, may determine its position usinga UE based positioning method or a UE assisted positioning method. Witha UE based positioning method, the UE 105 computes a location of the UE105 (e.g. with the help of assistance data received from a locationserver such as LMF 124 or broadcast by SVs 102/202/302). With a UEassisted positioning method, the UE 105 may send the locationmeasurements to a location server (e.g. LMF 124) for computation of alocation estimate for UE 105, which may be returned by the locationserver to UE 105.

At stage 5, a fixed serving cell and/or a fixed serving TA in which theUE 105 is located is determined by the UE 105 and/or by one more networkentities including sNB 106/202/307, AMF 122, and LMF 124, based on theposition of the UE obtained at stage 4 and the configuration informationfor the fixed cells and the fixed TA. For example, as discussed abovefor FIGS. 17, 18 and 20, a grid point closest to the UE 105 location maybe used to determine a fixed serving cell and/or a serving TA.Alternatively, the location of the UE 105 may be converted to X and Ycoordinate indices and used to look up a serving cell and serving TAcode in a table, as described for FIG. 19. A network entity (e.g. the UE105, an sNB 106/202/307 or AMF 122) may generate a unique PLMNidentifier (e.g. a unique cell ID) for the fixed serving cell using thecell identifier for the fixed serving cell and, optionally, the colorcode for the fixed serving TA in which the UE 105 is located, asdescribed for FIG. 21.

At stage 6, the UE 105 sends a Registration Request message through anSV 102/202/302 and a serving sNB 106/202/307 to the AMF 122 of a PLMNthat is associated with the fixed serving cell and/or the fixed servingTA in which the UE 105 is located, as determined at stage 5. Theassociation of the PLMN to the fixed serving cell and/or the fixedserving TA may be part of the configuration data received at stage 1.

At stage 7, the AMF 122 returns a Registration Accept message to the UE105 through sNB 106/202/307 and SV 102/202/302. Stages 4-7 may berepeated to re-register with the same PLMN or register with a differentPLMN, e.g., if the UE 105 moves to a new serving TA for the same PLMN ormoves to a new serving TA that is associated with a different PLMN.

At stage 8, the UE 105 may make an emergency call to a PSAP associatedwith the fixed serving cell and/or fixed serving TA in which the UE 105is located. For example, the UE 105 may include the unique PLMNidentifier (e.g. a unique cell ID for the fixed serving cell), asdetermined at stage 5, in a SIP INVITE request that is sent to the PLMNthrough the SV 102/202/302 and sNB 106/202/307. The serving 5GCN 110,illustrated with AMF 122 and LMF 124 in FIG. 22 may then route the EMcall to a PSAP associated with the unique PLMN identifier.

At stage 9, the UE 105 may receive and display broadcast WEA messagesassociated with the fixed serving cell and/or the fixed serving TA,e.g., based on the unique PLMN identifier determined at stage 5. Forexample, the sNB 106/202/307 and SV 102/202/302 may broadcast a WEAmessage associated with the unique PLMN identifier. Alternatively, thesNB 106/202/307 and SV 102/202/302 may broadcast a list of applicableWEA message IDs for each unique PLMN identifier, e.g., in the DL signalsof stage 2, and may also provide the WEA messages separately, and the UE105 may display the appropriate WEA message(s) based on the unique PLMNidentifier.

At stage 10, the AMF 122 may provide UE related information, includingthe unique PLMN identifier for the UE 105, to law enforcement associatedwith the fixed serving cell or fixed serving TA. If the UE 105 movesinto a new fixed cell or new fixed TA and reports the movement to thePLMN, the AMF 122 may provide the updated UE information to lawenforcement associated with the new fixed cell or new fixed TA.

At stage 11, a handover of UE 105 within the serving PLMN or to a newserving PLMN may be performed, based on movement of UE 105 to a newfixed serving cell and/or a new fixed serving TA.

To support paging of a UE 105 in the same way as for terrestrial NRaccess, each sNB 106 (with transparent mode) or sNB-CU 307 (withregenerative mode with split architecture) may have a defined and wellknown service area comprising one or more fixed TAs. This may notpreclude supporting the same fixed TA by two or more sNBs 106 or two ormore sNB-CUs 307 or having some variation in the current radio coveragearea of an sNB 106/307 due to variation in the radio beams coverage ofSVs 102/302 controlled by the sNB 106/307. But it may preclude sNBs106/307 from shifting support between different fixed TAs at differenttimes.

With a well-defined association between fixed TAs and sNBs 106/307, aserving AMF 122 may direct a paging request for a UE 105 only to thosesNBs 106/307 supporting the current fixed TA for the UE 105 just as forpaging of a UE from certain gNBs 114 in the case of terrestrial NRaccess.

SNBs 106 (or sNB-CUs 307) may also broadcast, in a SIB for eachsupported radio cell, the fixed TA(s) currently supported by that radiocell. This may assist a UE 105 in determining its current fixed TA aswell indicating to a UE 105 whether a registration is needed for achange of TA.

The support of fixed TAs by sNBs 106 or sNB-CUs 307 may mean that atleast fixed TA areas must be known by sNBs 106 or sNB-CUs 307 in orderto determine the fixed TA(s) supported by each radio cell and tomaintain radio cell coverage within the supported fixed TA(s) only.

A serving AMF 122 may provide a geographic definition of the fixed TAsallowed for a UE 105 and associated fixed cells as part of Registration.This data may be pre-configured in an AMF 122 and may not need to beinterpreted or processed—making support quite simple.

A UE 105 with a location capability may periodically determine itscurrent fixed TA and current fixed serving cell. The current fixed TAmay be used to determine when a new registration is needed, e.g., if aUE 105 moves outside of its allowed set of fixed TAs. The current fixedserving cell may be used to support regulatory services as describedelsewhere herein and may also be included for mobile originatingservices where defined in order to provide location information to thenetwork (e.g., a 5GCN 110 and/or NG-RAN 112).

For a UE 105 without a location capability, an sNB 106 or sNB-CU 307 maydetermine a current fixed TA and possibly a current fixed cell from thecurrent radio cell and radio beam used by a UE 105. This may be enoughto support UE 105 access though regulatory services may be provided lessprecisely.

Aspects of SOLUTION 2, which may be used to support transfer of bothtransparent SVs and regenerative SVs from a first earth station to asecond earth station, are next discussed with reference to FIGS. 23 to36.

An orbiting SV 102/202/302 that is in a LEO or MEO will typicallycommunicate with an ES 104 (or possibly several ESs 104) that is in LineOf Sight (LOS) to the SV 102/202/302. The SV 102/202/302 may remain incommunication with the ES 104 for a period P and over an orbitaldistance D that depends on the height of the SV 102/202/302 above groundlevel, the perpendicular distance of the ES 104 from the orbital planeof the SV 102/202/302, as measured over the surface of the Earth, andthe minimum angle of elevation of the SV 102/202/302 as seen from the ES104 for which communication remains possible. A typical minimum angle ofelevation may be around 10 degrees and a typical SV 102/202/302 heightfor a LEO orbit may be around 600 to 1200 kilometers. Under theseconditions, the period of communication P may be in the range of 5 to 15minutes and the associated orbital distance D may be in the range of2000 to 6500 kilometers for an ES 104 that is within 2500 kilometers(for an SV height of 1200 kilometers) or 1500 kilometers (for an SVheight of 600 kilometers) of the SV 102/202/302 orbital plane. Followingthe period of communication P, the SV 102/202/302 would need to betransferred to a new ES 104 (or several new ESs 104). Alternatively,signaling related to radio cells supported by the SV 102/202/302 mightbe transferred one at a time or in batches to a new ES 104 in order toavoid transfer of all the signaling for the SV 102/202/302 at the sametime, which might be more disruptive to UEs 105 currently accessing theSV 102/202/302. In either case, however, the transfer of an SV101/202/302 and/or of radio cells for the ES 102/202/302 from one ES 104to another ES 104 may be disruptive to UEs 105 currently accessing theSV 102/202/302 due to a need to reestablish a new SV-ES radio link andreestablish signaling connections for the UEs 105.

Static radio cell planning may be used for terrestrial networks andpossibly GEO SVs 102/202/302. For example, the location, coverage,capacity, operating times and other parameters of radio cells forterrestrial networks and possibly GEO SVs 102/202/302 may be defined andreevaluated periodically (e.g., monthly) and may remain fixed betweensuccessive evaluations.

Dynamic radio cell planning may be used for networks of LEO (and MEO)SVs 102/202/302. For transparent SVs 102, a radio cell definition mayremain fixed only for short periods, e.g., for a time period duringwhich a radio cell is supported by the same earth station 104 and/or bythe same sNB 106. For example, radio beams supported by an SV 102 couldremain static and might be assigned to radio cells for a period duringwhich the radio cells are supported by the same ES 104 and same sNB 106.When an SV 102 or signaling for an SV 102 is transferred to a new ES 104and possibly a new sNB 106, the static radio beams might be transferredto support a new set of radio cells, thereby also changing the radiocells. This may lead to short term radio cells with lifetimes of theorder of a few minutes (e.g. 5 to 15 minutes).

For regenerative SVs 202 and 302, radio cell definitions may remainfixed for longer periods, although the locations and countries in theradio cells' coverage areas may change.

An SVO may need to develop a global (or regional) radio cell plan basedon known SV 102/202/302 orbits and MNO demands in different countriesand regions at different times of day and days of the week. The radiocell plan may have location, time and SV dimensions, with radio cellsbeing defined for each SV 102/302/302 for each of different time periodsand for each of different location areas. For example, the plan maydefine radio cells for each SV 102/202/302 for a sequence of times (andassociated locations of the SV), e.g., taking into account the transferof each SV 102/202/302 between earth stations 104 and transfer of accessto the SV 102/202/302 between sNBs 106/202/307 and/or between 5GCNs 110.The definition of each radio cell may include defining constituent radiobeams, radio beam directions, frequencies, bandwidth, Physical Cell IDs(PCIs), power, etc. The plan may be used to predetermine transfers ofradio cells and SVs 102/202/302 between earth stations (ESs) 104 andsNBs 106/202/307. For example, an SVO operation and maintenance (O&M)server may deliver information to ESs 104, SVs 102/202/302 and sNBs106/202/307 to assist in transferring radio cells and SVs 102/202/302between earth stations ES and sNBs 106/202/307. The information mayindicate when the transfer needs to occur and may provide otherinformation regarding the transfers including identifying and definingthe radio cells and SVs 102/202/302. For example, the information may beprovided for a period of 1-30 days in advance.

As discussed below, handovers (also referred to as transfers), for bothtransparent SVs 102 and regenerative SVs 202/302, may transfer an SV102/202/302 from one earth station 104 to another and may also transferthe SV 102/202/302 from one sNB 106/202/307 to another sNB 106/202/307and/or from one 5GCN 110 to another 5GCN 110. The handovers may allowUEs 105 to continue to access the SV 102/202/302 before, during andafter the handover with limited interruption of voice, data andsignaling communication using the same the radio cells, which maycomprise one or more radio beams supported by the SV 102/202/302. In oneimplementation, a handover may occur without requiring UEs 105 to changeradio cells. For example, signaling may be transported between a firstplurality of UEs 105 and a Core Network, e.g., a 5GCN 110, at a firsttime, during which the signaling is transported via the SV 102/202/302,a first earth station 104 and a first network node, such as an sNB 106,an SV-sNB 202, an SV-sNB-DU 302, or an sNB-CU 307. The signaling istransported between the SV 102/202/302 and the first plurality of UEs105 using a first plurality of radio cells. The signaling, for example,may include user plane signaling and control plane signaling, e.g.,where the user plane signaling includes signaling for data and voiceconnections between the UEs 105 and external entities, and the controlplane signaling includes signaling for connections and associationsbetween the UEs 105 and entities in the Core Network (e.g., such as AMF122 and SMF 134). At a second time, the transport of the signalingbetween the first plurality of UEs 105 and the Core Network may cease.Subsequently, the transport of signaling between the first plurality ofUEs 105 and the Core Network is enabled via the SV 102/202/302, a secondearth station 104 and a second network node, which may be the samenetwork node (e.g., an sNB 106, sNB 202, sNB-CU 307 or sNB-DU 302), ordifferent than the first network node, where the signaling istransported between the SV 102/202/302 and the first plurality of UEs105 using the first plurality of radio cells.

In some implementations, the handover may occur with some UEs 105changing radio cells. For example, signaling may be transported betweena second plurality of UEs 105 and the Core Network at the first time,during which the signaling is transported via the SV 102/202/302, thefirst earth station 104 and the first network node and is transported(between the SV 102/202/302 and the second plurality of UEs 105) using asecond plurality of radio cells. The second plurality of UEs 105 may behanded over to a third plurality of radio cells supported by one or morenew SVs 102/202/302 that are different from the SV 102/202/302 beforethe second time, i.e., before the transport of the signaling between thesecond plurality of UEs 105 and the Core Network ceases. Signaling istransported between the second plurality of UEs 105 and the Core Networkafter the second time, with the signaling being transported via the oneor more new SVs 1023/202/302 using the third plurality of radio cells.

FIG. 23 is a block diagram illustrating a communication system 2300using transparent SVs, including entities such as those illustrated inFIG. 1. The communication system 2300, for example, includes an sNB1,which may be sNB 106, a first earth station ES1 and a second earthstation ES2, which may be earth stations 104-1 and 104-2, a spacevehicle SV, such as a transparent SV 102, and a UE 105. While only oneUE 105 is illustrated, it should be understood that a plurality of UEsusing one or more radio cells may be part of communication system 2300.As illustrated, the same SV 102 is shown at a time T1 and at a latertime T2. FIG. 23 illustrates a procedure for intra-sNB radio cell and/orSV transfer between the earth stations ES1 and ES2 for a transparent LEOSV, such as SV 102.

As illustrated, signaling for a radio cell 1 from SV 102 may passthrough earth station ES1 from time T1 to time T2. The radio cell 1 mayinclude one or more radio beams supported by the SV 102. At time T2,signaling for radio cell 1 is transferred from earth station ES1 toearth station ES2, i.e., the signaling between UE 105 and a 5GCN 110(not shown) through the earth station ES1 ceases, and is establishedthrough earth station ES2. For example, the SV 102 may no longer beaccessible from earth station ES1 at time T2, thus, requiring thetransfer to earth station ES2. If the SV 102 is restricted totransferring data and signaling from and to only one earth station at atime, all radio cells for the SV 102 would be transferred to earthstation ES2 at or around time T2, which may be equivalent totransferring (or handing over) the entire SV 102 (or all signaling forthe SV 102) from ES1 to ES2. The signaling for radio cell 1 may includeuser plane signaling and control plane signaling for one or more UEs 105accessing radio cell 1, where the user plane signaling includessignaling for data and voice connections between each of the UEs 105 andexternal entities, and where the control plane signaling includessignaling for connections and associations between each of the UEs 105and entities in a serving 5GCN 110.

Various transfer options may be employed for the intra-sNB radio celltransfer. In one implementation, the radio cell may be changed attransfer. For example, radio cell 1 may be “switched off” at or justbefore time T2, and a new radio cell (radio cell 2) may be started(initialized) at or just after time T2 using earth station ES2. Theradio cell 2, for example, may differ from radio cell 1 in one or moreaspects. For example, radio cell 2 may include at least one of adifferent physical cell identity (PCI), a different global cell identity(e.g. a different radio cell ID), one or more different radio beams, oneor more different radio beam directions, one or more different frequencybands, one or more different bandwidths, or a combination thereof. AllUEs previously accessing radio cell 1 may be handed off to other radiocells, i.e., a handover procedure may be performed to transfer the UE105 to another radio cell (and another SV 102 if necessary) prior to theintra-sNB radio cell transfer at time T2.

In another implantation, the radio cell may continue, i.e., remainunchanged after transfer, in which case radio cell 2 may be the same asradio cell 1. For example, as illustrated in FIG. 23, radio cell 1 maybe transferred to earth station ES2 at time T2, but may continueunchanged via earth station ES2 except for, e.g., a change in signaltiming and possibly a short period of no transmission. If the radio cellcontinues, some or all of the UEs previously accessing radio cell 1 mayremain with radio cell 1 following radio cell transfer. For example, UE105 may remain with the radio cell 1 following the radio transfer to theearth station ES2 at time T2.

FIG. 24 is a block diagram illustrating a communication system 2400using transparent SVs, including entities such as those illustrated inFIG. 1. Communication system 2400 is similar to communication system2300, and may include a first sNB1 and second sNB2, which may be sNB106-1 and sNB 106-2, a first earth station ES1 and a second earthstation ES2, which may be earth stations 104-1 and 104-2, a transparentspace vehicle SV, such as SV 102, a 5G core network, e.g., 5GCN 110, incommunication with both sNB1 and sNB2, and a UE 105. As illustrated, thesame SV 102 is shown at time T1 and at time T2. FIG. 24 illustrates aprocedure for inter-sNB radio cell (or SV) transfer between earthstations ES1 and ES2 for transparent LEO SVs, such as SV 102.

The inter-sNB radio cell transfer may be similar to the intra-sNB radiocell transfer discussed above in FIG. 23, but includes a change of radiocell support from sNB1 to sNB2 at time T2. Thus, at time T2 signalingfor a radio cell 1 from SV 102 is transferred from earth station ES1 andsNB1 to earth station ES2 and sNB2. As illustrated, the core network,5GCN 110 remains unchanged after the radio cell transfer at time T2.

Due to the change of sNB from sNB1 to sNB2 at time T2, the continuationof the radio cell at sNB2 after time T2 may not be performed (e.g. maynot be feasible). Thus, the radio cell may be changed at transfer, i.e.,radio cell 1 would be changed to a different radio cell 2 at sNB2 attime T2. For example, the radio cell 2 may have a different physicalcell ID and/or a different global cell ID than radio cell 1, e.g. aglobal cell ID for radio cell 2 may include a cell ID that includes anID for sNB2, while a global cell ID for radio cell 1 may include a cellID that includes an ID for sNB1. All of the UEs previously accessingradio cell 1 may be handed off to other radio cells, and other SVs 102if necessary, prior to the radio cell transfer at time T2. This meansthat a UE 105 may not need to be transferred along with the radio cellat time T2.

FIG. 25 is a block diagram illustrating a communication system 2500using transparent SVs including entities such as those illustrated inFIG. 1. The communication system 2500, is similar to communicationsystems 2300 and 2400, and may include a first sNB1 and a second sNB2,which may be sNB 106-1 and sNB 106-2, a first earth station ES1 and asecond earth station ES2, which may be earth stations 104-1 and 104-2, atransparent space vehicle SV, such as SV 102, two 5G core networks 5GCN1and 5GCN2, which may be 5GCN 110-1 and 5GCN 110-2, that are respectivelyassociated with sNB1 and sNB2, and a UE 105. As illustrated, the same SV102 is shown at time T1 and at time T2. FIG. 25 illustrates a procedurefor inter-PLMN radio cell transfer between earth stations ES1 and ES2for transparent LEO SVs, such as SV 102.

The inter-PLMN radio cell transfer may be similar to the inter-sNB radiocell transfer discussed above in FIG. 24, but includes a change of corenetworks, e.g., 5GCN1 and 5GCN2 along with the change from sNB1 to sNB2at time T2. Thus, at time T2 signaling for a radio cell 1 from SV 102 istransferred from earth station ES1, sNB1 and associated 5GCN1 to earthstation ES2, sNB2, and associated 5GCN2. By way of example, in onescenario, the locations of sNB1 and sNB2 may be in different countries,thus, prompting a change in the core network at the time of transfer. Inanother scenario, there may be different licensed coverage areas for5GCN1 and 5GCN2 again prompting a change in the core network at the timeof transfer.

Due to the change of both sNB and 5GCN, continuation of the radio cellat sNB2 after transfer is typically not feasible. Accordingly, radiocell 1 is changed to a different radio cell 2 at sNB2 when the transferoccurs at time T2. All UEs previously accessing radio cell 1 may behanded off to other radio cells, and others SVs 102 if necessary, thatare associated with 5GCN1 prior to radio cell transfer at time T2.

For intra-sNB transfer, e.g., as illustrated in FIG. 23, and possiblyfor inter-sNB transfer, e.g., as illustrated in FIG. 24, continuation ofa radio cell may be possible. Continuation of a radio cell may allowsome or all UEs that were previously accessing the radio cell to remainwith the radio cell following the transfer. If continuation of the radiocell is employed, all of these UEs would need to reacquire the radiocell at about the same time, i.e., around the transfer time T2 shown inFIGS. 23 and 24, which may load the system.

In one implementation (referred to as implementation I3) for continuinga radio cell on behalf of a plurality of UEs 105, which continue toaccess the radio cell following a transfer of the radio cell as shown inFIGS. 23 and 24, NR physical layer cell timing (referred to as “NRtiming” or just as “timing”) for the radio cell after the transfer attime T2 may be determined, e.g., calculated by the sNB1 shown in FIGS.23 and 24, based on known, calculated or measured propagation andtransmission delays for sNB to ES, ES to SV, and SV to UE links. Forexample, the timing may be determined based on a known orbital positionof the SV 102, and known, measured or calculated propagation andtransmission delays for signaling links between: sNB1 and ES1; ES1 andSV 102; sNB1 (or sNB2) and ES2; ES2 and SV 102; and SV 102 and theplurality of UEs. The new NR timing and the time at which it will occur(e.g. time T2) may be provided to each UE 105 in the plurality of UEs105 by the sNB (e.g., sNB1) prior to the radio cell transfer at time T2.For example, the new NR timing may be provided relative to the previousNR timing as an offset (e.g. an addition or subtraction) to the previoustiming. Knowledge of the new NR timing for the radio cell after thetransfer at time T2 may enable each of the plurality of UEs 105 toquickly acquire and access the radio cell after time T2, which may avoidor reduce loss or delay of signaling content. Alternatively, in anotherimplementation (referred to as implementation I4), NR timing for theradio cell following transfer may be aligned with the NR timing prior totransfer by avoiding any (significant) change in timing after the radiocell transfer at time T2. This alignment may use the new NR timingdetermined as described above to calculate a timing correction for thenew NR timing which is implemented at the sNB1 or sNB2 at time T2 tocancel out the change in NR timing which would otherwise have occurredat time T2. In this case, the plurality of UEs 105 may not need to beinformed of a change in NR timing and may continue to access the radiocell after time T2 without any significant change in their timing.Additionally or alternatively, in another implementation (referred to asimplementation I5), a timing advance (TA) for each UE 105 in theplurality of UEs 105 that is applicable after the transfer at time T2may be determined, e.g., calculated by the sNB1, and may be provided toeach UE 105 prior to transfer at time T2.

One or more of implementations I3, I4 and I5 may enable transfer of anRRC signaling link for each UE 105 in the plurality of UEs 105 to theradio cell following transfer of an SV 102 at time T2 and with a briefinterruption at the PHY, MAC and RLC layers and with the RLC layer beingused to reestablish signaling and data communication for each UE 105when there is a temporary loss of signaling. In some implementationswhere the RRC signaling link for a UE 105 cannot be transferred to theradio cell after time T2, the UE 105 may need to reestablish an RRCsignaling connection with the sNB1 or sNB2 following radio cell transferin a manner similar to handover of a UE to a new radio cell.

A change of radio cell may be used for intra-sNB transfer, e.g., asillustrated in FIG. 23, inter-sNB transfer, e.g., as illustrated in FIG.24, and inter-PLMN transfer, as illustrated in FIG. 25. With a change ofradio cell, the new radio cell 2 in FIGS. 23-25 differs from theoriginal radio cell 1. A change of a radio cell may provide anopportunity to change radio cell parameters, such as the cell coveragearea, cell ID, cell frequencies and bandwidth. UEs 105 may be offloadedgradually from the radio cell a short time before transfer, e.g., usinga standard handoff procedure. In some implementations, radio cells mayhave a lifetime of up to 5-15 minutes, due to use of the same sNB 106and same earth station 104, and, thus, UE 105 handoff operations due toradio cell transfer may be relatively infrequent compared to UE 105handoff due to movement of the radio cell itself while supported by thesame earth station 104. For example, for a moving radio cell, e.g., aradio cell produced without using a steerable SV antenna, the handoffinterval for any UE 105 may be in the range 6-140 seconds, making amoving radio cell the predominate cause of handover for any UE 105.

FIG. 26 is a block diagram illustrating a communication system 2600applicable to regenerative SVs with a non-split architecture, includingentities such as those illustrated in FIG. 2. Communication system 2600may include a first earth station ES1 and a second earth station ES2,which may be earth stations 104-1 and 104-2, a 5G core network, e.g.,5GCN 110, that is in communication with both earth stations ES1 and ES2,a space vehicle SV/sNB that includes an sNB, such as SV 202 thatincludes an sNB 202, and a UE 105. While only one UE 105 is illustrated,it should be understood that a plurality of UEs using one or more radiocells may be part of communication system 2300. As illustrated, the sameSV/sNB 202 is illustrated at a time T1 and at a later time T2. FIG. 26illustrates a procedure for transfer of regenerative SVs, such as SV/sNB202, between earth stations ES1 and ES2, where there is no change in the5GCN.

All radio cells terminate in the SV/sNB 202, and accordingly, transferof individual radio cells from ES1 to ES2 does not occur since the radiocells are not defined on links to and from ES1 and ES2. Accordingly, inone implementation, signaling applicable to all radio cells, includingall CP/UP signaling carried by the SV/sNB 202, may be transferred fromearth station ES1 to earth station ES2 at time T2. A 5GCN 110 feederlink thus also changes at time T2 from earth station ES1 to earthstation ES2. UEs previously accessing SV/sNB 202, e.g., UE 105, maycontinue to access the SV/sNB 202 after time T2 as the NR radiointerface between the UEs and SV/sNB 202 is not impacted. Thus, the UE105 may experience only a brief period of delay at the transfer time T2.If the AMF 122, SMF 134 and UPF 130 for each UE 105 remains the samefollowing the transfer at time T2, the UE 105 may continue tocommunicate via the SV/sNB 202 without changing radio cells. If,however, the AMF 122, SMF 134 and/or UPF 130 for a UE 105 needs tochange, then the UE 105 may be handed off to a different radio cell (orthe same radio cell) at or prior to the time T2 using an explicithandoff procedure which may allow for change of the AMF 122, SMF 134and/or UPF 130.

FIG. 27 is a block diagram illustrating a communication system 2700applicable to regenerative SVs with a non-split architecture, includingentities such as those illustrated in FIG. 2. Communication system 2700is similar to communication system 2600, but includes a first 5G corenetwork 110, e.g., 5GCN1, associated with earth station ES1 and a second5G core network 110, e.g., 5GCN2, associated with earth station ES2.FIG. 27 illustrates a procedure for transfer of regenerative SVs, suchas SV/sNB 202, between earth stations ES1 and ES2, where there is achange of 5GCN 110.

As illustrated in FIG. 27, at transfer time T2, the CP/UP signalingcarried by the SV/sNB 202 is transferred from earth station ES1 and5GCN1 to earth station ES2 and 5GCN2. Thus, in the procedure illustratedin FIG. 27, transfer of UEs along with the SV/sNB is no longer possible.In one implementation, the SV/sNB 202 may initiate handoff of all UEs toother radio cells (and other SV/sNBs 202) prior to the transfer to earthstation ES2 at time T2. In one example, the SV/sNB 202 may also releasethe NG interface to the first 5GCN1 and setup a new NG interface to thesecond 5GCN2.

FIG. 28 is a block diagram illustrating control plane protocol layering2800, and FIG. 29 is a block diagram illustrating user plane protocollayering 2800 applicable to the CP/UP signaling 1 and CP/UP signaling 2shown in FIG. 26 before and after transfer of the CP/UP signaling. Thecontrol plane (CP) protocol layering 2800 is illustrated between UE 105,SV/sNB 202, earth station 104 (which may be ES1 or ES2), and 5GCN,illustrated by AMF 122 and SMF 134, with the earth station 104 acting asa Level 2 Relay, although it could alternatively act as a Level 1 relay(in which case the L2 level shown in FIG. 28 for ES 104 would not bepresent). The user plane (UP) protocol layering 2900 is illustratedbetween UE 105, SV/sNB 202, earth station 104, and 5GCN 110, illustratedwith UPF (VPLMN) 130, and UPF (anchor) 130 in a home network for UE 105,with earth station 104 acting as a Level 2 Relay, although it couldalternatively act as a Level 1 relay (in which case the L2 level shownin FIG. 29 for ES 104 would not be present).

FIGS. 28 and 29 may apply to the transfer of signaling for SV/sNB 202shown in FIG. 26, with correspondence of the UE 105 and SV/sNB 202 shownin the figures, with AMF 122, SMF 134 and UPF (VPLMN) 130 in FIGS. 28and 29 being part of 5GCN 110 in FIG. 26, and with UPF (anchor) 130 inFIG. 29 being part of a home 5GCN 110 for UE 105 (not shown in FIG. 26).If UE 105 is not roaming, UPF (VPLMN) 130 in FIG. 29 may be absent andis hence shown using dashed lines. Additionally, ES 104 in FIGS. 28 and29 may correspond to ES1 in FIG. 26 prior to time T2 and to ES2 in FIG.26 at and after time T2. The protocol layering shown in FIGS. 28 and 29corresponds to that defined by 3GPP for NR (e.g. in TS 23.501 and TS28.300) as is well known to those with ordinary expertise.

In FIG. 28 both the UE 105 and sNB 202 CP interactions with the 5GCN 110are shown (superimposed). The earth station 104 may act as a Level 1relay or Level 2 relay (as shown) for both CP and UP. For relayingthrough the earth station 104, non-3GPP protocols may be used at L1 andL2, as indicated with shading.

When the SV/sNB 202 is transferred to a new earth station 104 (i.e. toES2 in FIG. 26) and if the 5GCN 110, illustrated as AMF(s) 122, SMF(s)134, and UPF(s) 130 in FIGS. 28 and 29, remains unchanged for all UEsaccessing the SV/sNB 202 which are also being transferred, then allprotocol layers shown in FIGS. 28 and 29 may remain unaffected exceptfor L1 and L2 through the earth station 104, indicated with shading. Inimplementations where the earth station 104 acts as an L1 relay, L2 datalinks between the SV/sNB 202 and 5GCN 110 may employ error correction toavoid duplication and/or loss of signaling data. In implementationswhere the earth station 104 acts as an L2 relay, old L2 links for theold earth station (ES1) may be released and new L2 links for the newearth station (ES2) may be setup.

Thus, in FIG. 26, where the CP/UP signaling is transported via theSV/sNB 202 in regenerative mode, the earth stations ES1 and ES2 may actas Level 1 relays. After the transfer at time T2, data links may betransferred from earth station ES1 to earth station ES2, where each datalink may include a Level 2 connection between the sNB 202 in the SV/sNB202 and the 5GCN 110. The signaling for each data link may betransported through the earth station ES1 at a Level 1 prior to thetransfer time T2 and transported through the earth station ES2 at aLevel 1 after the transfer time T2.

In another implementation, the earth stations ES1 and ES2 may act asLevel 2 relays. For example, immediately prior to the transfer time T2,data links between the sNB 202 in the SV/sNB 202 and the 5GCN 110 may bereleased, where the data links transport signaling, and each data linkincludes a Level 2 connection between the sNB 202 in the SV/sNB 202 andthe earth station ES1 and a concatenated Level 2 connection between theearth station ES1 and the 5GCN 110. At the transfer time T2, a Level 1transport of signaling between the sNB 202 in the SV/sNB 202 and the5GCN 110 is transferred from the earth station ES1 to the earth stationES2. Immediately after the transfer time T2, data links between the sNB202 in the SV/sNB 202 and the 5GCN 110 are established, where the datalinks transport signaling and include a Level 2 connection between thesNB 202 in the SV/sNB 202 and the earth station ES2 and a concatenatedLevel 2 connection between the earth station ES2 and the 5GCN 110. Eachdata link after the transfer at time T2 may correspond to a data linkprior to the transfer.

FIG. 30 shows a signaling flow 3000 that illustrates the transfer ofdata links for SV/sNB 202 at the transfer time T2 discussed for FIGS.26, 28 and 29, and includes an SV/sNB 202, a first earth station ES1104-1, a second earth station ES2 104-2, and 5GCN 110 that maycorrespond to like numbered entities in FIGS. 26, 28 and 29. Moreover,5GCN 110 in FIG. 30 may correspond to any of AMF 122 or either of UPFs130 in FIGS. 28 and 29. The signaling flow 3000 illustrates the transferof a data link for earth stations acting as L1 Relays, and specifically,how an L2 data link for either UP or CP protocol layering may betransferred when an SV/sNB 202 is transferred between earth stations ES1104-1 and ES2 104-2 with the earth stations acting as L1 relays. TheSV/sNB 202, earth stations ES1 104-1 and ES2 104-2, and 5GCN 110 (e.g.,AMF 122 or UPF 130) are assumed to be synchronized to a common time witharound 1 millisecond (ms) accuracy in order to enable transfer ofsignaling in a precisely time coordinated manner.

At stage 1 in FIG. 30, at time T1, a data link between the SV/sNB 202and the 5GCN 110 is present and is relayed at L1 by the earth station104-1.

At stage 2, a control procedure is performed by SV/sNB 202 and the 5GCN110 (e.g. AMF 122 or UPF 130) to agree to the transfer of the data linkfrom transport via earth station 104-1 to transport via earth station104-2 at time T2. The control procedure may be performed using signalingbetween SV/sNB 202, the ESs 104-1 and 104-2 and the 5GCN 110 (e.g. AMF122 or UPF 130) at the L2 level and/or at other protocol levels.

At stage 3, at time T2-t, the SV/sNB 202 and the 5GCN 110 each send alast UL and DL portion of signaling data, respectively, to the earthstation 104-1 followed by an End Data marker in each case, which may be,e.g., an L2 control frame or a sequence of L2 control frames. In thiscontext, UL signaling data refers to signaling that is sent by one ormore UEs 105 to 5GCN 110 (e.g. AMF 122 or UPF 130) via SV/sNB 202 and ES104-1 or ES 104-2, and DL signaling data refers to signaling that issent by 5GCN 110 (e.g. AMF 122 or UPF 130) to one or more UEs 105 viaSV/sNB 202 and ES 104-1 or ES 104-2. The time T2, for example, maycorrespond to the time of transfer of the SV/sNB 202 in FIG. 26. Thetime period t, may slightly exceed the end to end transport delaybetween the SV/sNB 202 and 5GCN 110 at L2, which may be calculated ormeasured.

At stage 4, the last UL and DL portions of signaling data are forwardedto the 5GCN 110 and SV/sNB 202, respectively, by the earth station 104-1followed by the End Data markers.

At stage 5, at time T2, the L1 transport for the data link istransferred from earth station 104-1 to earth station 104-2 (e.g. asagreed and coordinated at stage 2).

At stage 6, the SV/sNB 202 and 5GCN 110 (e.g. AMF 122 or UPF 130) eachsend a Start Data marker to the earth station 104-2 followed by new ULand DL data.

At stage 7, the Start Data markers are forwarded by the earth station104-2 to the SV/sNB 202 and 5GCN 110 followed by the new UL and DL data.

Resumption of data transfer after time T2 at stages 6 and 7 may lead toa time period t during which no UL or DL data is sent and received,which may cause an extra delay t in signaling transfer for higherprotocol levels. In an optimization to reduce or eliminate most of thisextra delay, the SV/sNB 202 and 5GCN 110 (e.g., AMF 122 or UPF 130) mayeach start to receive data via earth station 104-2 at time T2, but mayeach start to send data via earth station 104-2 (e.g. at stage 6 and 7)at time T2−t*, where t* is the lesser of t and the calculated end to endtransmission delay via earth station 104-2.

FIG. 31 shows a signaling flow 3100 that illustrates the transfer ofdata links for SV/sNB 202 at the transfer time T2 discussed for FIGS.26, 28 and 29, and includes an SV/sNB 202, a first earth station ES1104-1, a second earth station ES2 104-2, and 5GCN 110 that maycorrespond to like numbered entities in FIGS. 26, 28 and 29. Moreover,5GCN 110 in FIG. 30 may correspond to any of AMF 122 or either of UPFs130 in FIGS. 28 and 29. The signaling flow 3100 illustrates the transferof a data link for earth stations acting as L2 Relays, and specifically,how a pair of concatenated L2 data links for either UP or CP protocollayering may be transferred when an SV/sNB 202 is transferred betweenearth stations ES1 104-1 and ES2 104-2 with the earth stations acting asL2 relays. The SV/sNB 202, earth stations 104-1 and 104-2, and 5GCN 110(e.g., AMF 122, UPF 130) are assumed to be synchronized to a common timewith around 1 ms accuracy in order to enable transfer of signaling in aprecisely time coordinated manner.

At stage 1 in FIG. 31, at time T1, one or more data links between theSV/sNB 202 and earth station 104-1 and concatenated data links betweenearth station 104-1 and the 5GCN 110 (e.g., AMF 122, UPF 130) arepresent and carry signaling data for UEs 105 which access SV/sNB 202.For each data link DL1 between the SV/sNB 202 and earth station 104-1,there is one concatenated data link DL2 between the earth station 104-1and the 5GCN 110 (e.g., AMF 122, UPF 130), such that data transferredfrom SV/sNB 202 to earth station 104-1 over DL1 is forwarded by ES 104-1to 5GCN 110 over DL2, and data transferred from 5GCN 110 to earthstation 104-1 over DL2 is forwarded by ES 104-1 to SV/sNB 202 over DL1.FIG. 31 shows how just one pair of concatenated data links (e.g. DL1 andDL2) are transferred from ES 104-1 to ES 104-2, but may be repeated tosupport the transfer of any number of pairs of concatenated data links.

At stage 2, a control procedure is performed by SV/sNB 202, the ESs104-1 and 104-2 and the 5GCN 110 (e.g. AMF 122 or UPF 130) to agree tothe transfer of the pair of concatenated data links from earth station104-1 to earth station 104-2 at time T2. The control procedure may beperformed using signaling between SV/sNB 202, the ESs 104-1 and 104-2and the 5GCN 110 (e.g. AMF 122 or UPF 130) at the L2 level and/or atother protocol levels.

At stage 3, at time T2-t, the SV/sNB 202 and the 5GCN 110 each send alast UL and DL portion of signaling data, respectively, to the earthstation 104-1 (over each of the data links) followed by an End Datamarker in each case, which may be, e.g., an L2 control frame or asequence of L2 control frames. In this context (e.g. as in FIG. 30), ULsignaling data refers to signaling that is sent by one or more UEs 105to 5GCN 110 (e.g. AMF 122 or UPF 130) via SV/sNB 202 and ES 104-1 or ES104-2, and DL signaling data refers to signaling that is sent by 5GCN110 (e.g. AMF 122 or UPF 130) to one or more UEs 105 via SV/sNB 202 andES 104-1 or ES 104-2. The time T2 may correspond to the time of transferof the SV/sNB 202 in FIG. 26. The time t, may slightly exceed the end toend transport delay between the SV/sNB 202 and 5GCN 110 at L2, which maybe calculated or measured.

At stage 4, the last UL and DL portions of signaling data and the EndData markers are relayed by the earth station 104-1 to the 5GCN 110 andSV/sNB 202, respectively. The ES 104-1 then sends a Disconnect frame toeach of 5GCN 110 and SV/sNB 202 to release both data links.

At stage 5, at time T2, L1 transport between 5GCN 110 and SV/sNB 202 istransferred from earth station 104-1 to earth station 104-2.

At stage 6, which may occur at time T or immediately after, the earthstation 104-2, the SV/sNB 202 and 5GCN 110 establish a new pair ofconcatenated data links between SV/sNB 202 and earth station 104-2 andbetween earth station 104-2 and the 5GCN 110 (e.g. as agreed andcoordinated at stage 2).

At stage 7, the signaling data transfer between 5GCN 110 and SV/sNB 202resumes on the new pair of concatenated data links, e.g., between theSV/sNB 202 and earth station 104-2 on one data link and between earthstation 104-2 and the 5GCN 110 on a second (concatenated) data link.

Resumption of data transfer at or just after time T2 at stages 6 and 7may lead to a time period t during which no UL or DL data is sent andreceived, which may lead to an extra delay t in signaling transfer forhigher protocol levels. Optimization may be possible if the SV/sNB 202is able to access both earth stations 104-1 and 104-2 for a short periodprior to time T2 to allow data transmission via earth station 104-2 tostart at time T−t* as for the L1 relay optimization described for FIG.30.

FIG. 32 is a block diagram illustrating a communication system 3200applicable to regenerative SVs with a split architecture, includingentities such as those illustrated in FIG. 3. Communication system 3200may include a first earth station ES1 and a second earth station ES2,which may be earth stations 104-1 and 104-2, an sNB-CU, such as sNB-CU307, that is in communication with both earth stations ES1 and ES2, aspace vehicle SV/sNB-DU that includes an sNB-DU, such as SV/sNB-DU 302,and a UE 105. While only one UE 105 is illustrated, it should beunderstood that a plurality of UEs using one or more radio cells may bepart of communication system 3200. As illustrated, the same SV/sNB-DU302 is illustrated at a time T1 and at a later time T2. FIG. 32illustrates a procedure for transfer of regenerative SVs with a splitarchitecture, such as SV/sNB-DU 302, between earth stations ES1 and ES2,where there is no change in the sNB-CU.

As illustrated in FIG. 32, the feeder link to access the combinedSV/sNB-DU 302 changes at time T2 from earth station 104-1 to earthstation 104-2. If the earth stations 104-1, 104-2 act as L1 or L2 relaysfor an interface (e.g. an F1 interface) between sNB-DU 202 and sNB-CU307, then UEs, such as UE 105, may remain with the SV/sNB-DU 302 with abrief delay in signaling and data transfer at protocol levels above L2.The procedures for regenerative SVs 202 illustrated by signaling flows3000 and 3100 in FIGS. 30 and 31 may be used to stop and restart CP andUP data and signaling transfer over the F1 interface when the SV/sNB 302transfer occurs. Specifically, signaling flows 3000 and 3100 may beapplicable, as described previously, when SV/sNB 202 is replaced bySV/sNB-DU 302 and 5GCN 110 is replaced by sNB-CU 307 in these signalingflows.

FIG. 33 is a block diagram illustrating a communication system 3300applicable to regenerative SVs with a split architecture, includingentities such as those illustrated in FIG. 3. Communication system 3300is similar to communication system 3200, but includes a first sNB-CU1,which may be sNB-CU 307-1, that is associated with earth station ES1 anda second sNB-CU2, e.g., which may be sNB 307-2, that is associated withearth station ES2, and both of which are associated with the same 5Gcore network 5GCN, e.g., which may be 5GCN 110. FIG. 33 illustrates aprocedure for transfer of regenerative SVs with a split architecture,such as SV/sNB-DU 302, between earth stations ES1 and ES2, where thereis a change of sNB-CU.

In one implementation, the SV/sNB-DU 302 may initiate handoff of all UEsthat are accessing SV/sNB-DU 302 prior to the transfer to earth station104-2 at time T2. In another implementation, a modified handoffprocedure may be used, as discussed below, to allow some or all UEs,e.g., a UE 105, to remain with the SV-sNB-DU 302 and a current radiocell for each of the UEs. In both implementations, the SV/sNB-DU 302 mayrelease an F1 interface to the old sNB-CU1 at or just before time T2 andset up a new F1 interface to the new sNB-CU2 at or just after time T2.

FIG. 34 is a block diagram illustrating control plane protocol layering3400, and FIG. 35 is a block diagram illustrating user plane protocollayering 3500 applicable to the CP/UP signaling 1 and CP/UP signaling 2shown in FIGS. 32 and 33 before and after transfer of the CP/UPsignaling. The control plane (CP) protocol layering 3400 is illustratedbetween UE 105, SV/sNB-DU 302, earth station 104 (which may be ES1 orES2), sNB-CU 307, and 5GCN 110 (which may be AMF 122 or SMF 130), withthe earth station 104 acting as a Level 2 Relay, although it mayalternatively act as a Level 1 relay (in which case the L2 level shownin FIG. 34 for ES 104 would not be present). The user plane (UP)protocol layering 3500 is illustrated between UE 105, SV/sNB-DU 302,earth station 104, and 5GCN, illustrated with UPF 130, with the earthstation 104 acting as a Level 2 Relay, although it could alternativelyact as a Level 1 relay (in which case the L2 level shown in FIG. 35 forES 104 would not be present). The CP and UP protocol layering in FIGS.34 and 35 is shown with L1 or L2 relaying through the earth station withlight shading.

FIGS. 34 and 35 may apply to the transfer of signaling for SV/sNB-DU 302shown in FIGS. 32 and 33, with correspondence of the UE 105 andSV/sNB-DU 302 shown in the figures. Additionally, ES 104 in FIGS. 34 and35 may correspond to ES1 in FIGS. 32 and 33 prior to time T2 and to ES2in FIGS. 32 and 33 at and after time T2. Similarly, sNB-CU 307 in FIGS.34 and 35 may correspond to sNB-CU 307 in FIG. 32, to sNB-CU1 307-1 inFIG. 33 prior to time T and to sNB-CU2 307-2 in FIG. 33 at and aftertime T2. The protocol layering shown in FIGS. 34 and 35 corresponds tothat defined by 3GPP for NR (e.g. in TS 23.501, TS 28.300 and TS 38.401)is well known to those with ordinary expertise.

In an implementation where the SV/sNB-DU 302 is transferred to a newearth station 104-2 and if the sNB-CU 307 remains unchanged for all UEsbeing transferred as in FIG. 32, all protocol layers may remainunaffected except for L1 and L2 through the earth station, shown withlight shading. The SV/sNB-DU 302 transfer may then be relatively simpleand may be similar that for the regenerative non-split architecture casedescribed above with reference to FIGS. 30 and 31.

In an implementation where the SV/sNB-DU 302 is transferred to a newearth station 104-2 and is also transferred to a new sNB-CU 307-2 as inFIG. 33, then a modified handoff procedure may be needed for UEs whichcontinue to access the SV/sNB-DU 302 and same radio cells after thetransfer at time T2. The modified handoff procedure may: (a) release oldnon-UE associated links and old non-UE associated connections betweenthe sNB-DU 302 and the old sNB-CU1 307-1; and (b) establish new non-UEassociated links and new non-UE associated connections between thesNB-DU 302 and the new sNB-CU2 307-2, for the protocol layersillustrated with light shading and medium shading, which comprise L1,L2, IP, UDP and SCTP (defined in IETF RFC 3286). The modified handoffprocedure may also release old UE associated connections and tunnels andestablish new UE associated connections and tunnels between the UE 105,sNB-DU 302, 5GCN 110, old sNB-CU1 307-1 and new sNB-CU2 307-2, for theprotocol layers illustrated with dark shading which comprise RRC(defined in 3GPP TS 38.331), PDCP (defined in 3GPP TS 38.323), F1AP(defined in 3GPP TS 38.473), SDAP (defined in 3GPP TS 37.324), NRUPP(defined in 3GPP TS 38.425), NGAP (defined in 3GPP TS 38.413) and GTP-U(defined in 3GPP TS 29.281).

Thus, in FIGS. 32 and 33, where the signaling (e.g. CP and UP signaling)is transported via the SV/sNB-DU 302 in regenerative mode, the sNB-DU302 communicates with an sNB-CU (e.g. sNB-CU 307 in FIG. 32 and sNB-CU1307-1 in FIG. 33) to transport the signaling to a 5GCN (e.g. 5GCN 110)before the transfer at time T2 and may communicate with the same sNB-CU(e.g. sNB-CU 307 in FIG. 32) or a different sNB-CU (e.g. sNB-CU2 307-2in FIG. 33) to transport signaling to the same 5GCN after the transferat time T2. In an implementation where the same sNB-CU is used totransport signaling before and after transfer time T2, e.g., asillustrated in FIG. 32, the earth stations ES1 and ES2 may act as Level1 relays, and data links from earth station ES1 may be transferred toES2 at the transfer time T2. Each data link may include a Level 2connection between the sNB-DU and the sNB-CU, and each data link istransported through the earth station ES1 at a Level 1 prior to thetransfer time T2 and is transported through the earth station ES2 at aLevel 1 after the transfer time T2.

In another implementation in which the same sNB-CU is used to transportsignaling before and after transfer time T2, e.g., as illustrated inFIG. 32, the earth stations ES1 and ES2 may act as Level 2 relays. Forexample, immediately prior to the transfer time T2, data links between anetwork node (which may be an sNB-DU, such as sNB-DU 302. or an sNB-CUsuch as sNB-CU 307 in FIG. 32 or sNB-CU 307-1 in FIG. 33) and the otherof the sNB-DU and the sNB-CU may be released, where the data linkstransport signaling, and each data link includes a Level 2 connectionbetween the network node and the earth station ES1 and a concatenatedLevel 2 connection between the earth station ES1 and the other of thesNB-DU and the sNB-CU. At the transfer time T2, a Level 1 transport ofsignaling between the network node and the other of the sNB-DU and thesNB-CU may be transferred from the earth station ES1 to the earthstation ES2. Immediately after the transfer time T2, data links betweenthe network node and the other of the sNB-DU and the sNB-CU may beestablished. The data links transport signaling and include a Level 2connection between the network node and the earth station ES2 and aconcatenated Level 2 connection between the earth station ES2 and theother of the sNB-DU and the first sNB-CU. Each data link after thetransfer at time T2 corresponds to a data link prior to the transfer.

In an implementation in which different sNB-CUs (e.g. sNBs-CUs 307-1 and307-2) are used to transport signaling before and after transfer timeT2, e.g., as illustrated in FIG. 33, the transport of signaling betweenthe UEs and the 5GCN after the transfer time T2 via the SV 302 may beenabled by performing a modified handover procedure for each UE (e.g. UE105). For example, the modified handover procedure for each UE mayinclude one or more of the following. Non-UE associated links andconnections between the sNB-DU (e.g. sNB-DU 302) and a first sNB-CU(e.g. sNB-CU 307-1 in FIG. 33) may be released immediately before thetransfer time T2, where signaling for the non-UE associated links andconnections is transported between the sNB-DU and the first sNB-CU viathe earth station ES1 at a Level 1 or a Level 2. Non-UE associated linksand connections between the sNB-DU and a second sNB-CU (e.g. sNB-CU307-2 in FIG. 33) may be established immediately after the transfer timeT2, where signaling for the non-UE associated links and connections istransported between the sNB-DU and the second sNB-CU via the earthstation ES2 at a Level 1 or a Level 2. UE associated connections andtunnels between the sNB-DU, the first sNB-CU and the 5GCN may bereleased immediately before the transfer time T2, where signaling forthe UE associated connections and tunnels is transported between thesNB-DU and the first sNB-CU using the non-UE associated links andconnections. UE associated connections and tunnels between the UEs,sNB-DU, the second sNB-CU and the 5GCN may be established immediatelyafter the transfer time T2, where signaling for the UE associatedconnections and tunnels is transported between the sNB-DU and the secondsNB-CU via the earth station ES2 using the non-UE associated links andconnections. The non-UE associated links and connections may include useof one or more of an Internet Protocol (IP), a User Datagram Protocol(UDP) and a Stream Control Transmission Protocol (SCTP). The UEassociated connections and tunnels may include use of one or more of aGPRS Tunneling Protocol (GTP), F1 Application Protocol (F1AP), PacketData Convergence Protocol (PDCP), Service Data Protocol (SDAP), RadioResource Control (RRC) protocol, Next Generation Application Protocol(NGAP) and NR User Plane Protocol (NRUPP).

FIG. 36A shows a signaling flow 3600 that illustrates various messagessent between components of a communication system, such as communicationsystems 300 and 3300 depicted in FIGS. 3 and 33. The signaling flow 3600illustrates a modified handover procedure to support transfer of a UE105 from a previous “source” sNB-CU (e.g. sNB-CU1 307-1 in FIG. 33) to anew “target” sNB-CU (e.g. sNB-CU2 307-2 in FIG. 33) when a servingSV/sNB-DU for the UE 105 (e.g. SV/sNB-DU 302 in FIG. 33) is transferredfrom a previous ES (e.g. ES1 104-1 in FIG. 33) to a new ES (e.g. ES2104-2 in FIG. 33). The signaling flow 3600 includes: (i) a source sNB3602 that includes the SV/sNB-DU before transfer (referred to asSV/sNB-DU 302), a source sNB-CU-User Plane (UP) 307-1UP, and a sourcesNB-CU-Control Plane (CP) 307-1CP; (ii) a target sNB 3604 that includesthe SV/sNB-DU after transfer (referred to as SV/sNB-DU 302′), a targetsNB-CU-UP 307-2UP, and a target sNB-CU-CP 307-2CP; and (iii) an AMF/UPF122/130 being accessed by the UE 105. An sNB-CU-UP for example, is alogical node hosting a user plane part of the PDCP protocol for ansNB-CU and the SDAP protocol for the sNB-CU. The sNB-CU-UP may terminatean E1 interface connected with an sNB-CU-CP and an F1-U interfaceconnected with an sNB-DU. An sNB-CU-CP is a logical node hosting the RRCand the control plane part of the PDCP protocol for the sNB-CU. ThesNB-CU-CP terminates an E1 interface connected with the sNB-CU-UP and anF1-C interface connected with an sNB-DU.

The stages described below for FIG. 36A may be similar or identical tothose used for terrestrial NR access by a UE 105 to support handover ofthe UE 105, referred to as “normal NR handover”, from one gNB to anothergNB, each using a split architecture. Differences (for the modifiedhandover procedure) to normal NR handover may arise for satellite NRaccess when a UE 105 continues to access the same sNB-DU when both thesNB-DU and the UE 105 are transferred to a new sNB-CU. The differencesto normal NR handover are described below.

At stage 1 in FIG. 36A, the source sNB-CU-CP 307-1CP may send a HANDOVERREQUEST message to the target sNB-CU-CP 307-2CP to request handover ofthe UE 105 (which is not shown in FIG. 36A) to the target sNB-CU 307-2.

At stage 2, the sNB-CU-CP 307-2CP sends a BEARER CONTEXT SETUP REQUESTmessage to the sNB-CU-UP 307-2UP containing address information to setupa bearer context for UE 105 in the sNB-CU-UP 307-2UP.

At stage 3, the sNB-CU-UP 307-2UP responds with a BEARER CONTEXT SETUPRESPONSE message containing address information for an F1-U interface tothe SV/sNB-DU 302′ and for an NG-U interface to the UPF 130.

Following stage 3 for normal NR handover, an F1 UE context setup wouldbe performed between a target gNB-CU-CP and a target gNB-DU. Thisprocedure is deferred to stage 12 here because the target SV/sNB-DU 302′does not become accessible from the target sNB-CU-CP 307-2CP until afterstage 8 in the modified handover procedure in FIG. 36A.

At stage 4, the target sNB-CU-CP 307-2CP responds to the sourcesNB-CU-CP 307-2CP with an HANDOVER REQUEST ACKNOWLEDGE message.

At stage 5, the F1 UE Context Modification procedure is performed tostop UL data transfer at the SV/sNB-DU 302 and for a change ofassociation from the sNB-CU 307-1. An indication (e.g. a Handovercommand) may also sent to the UE 105 by the SV/sNB-DU 302. Different tonormal NR handover, this indication indicates that handover is occurringto a new sNB-CU 307-2 but without change to the sNB-DU 302 and thatprotocol levels above RLC (e.g. PDCP, SDAP and RRC) will need to beresumed or restarted by the UE 105 and/or by new sNB-CU 307-2. Differentto normal NR handover, UE 105 does not then send a Random Access requestto an sNB-DU (e.g. sNB-DU 302) to change a radio cell and insteadremains on a current radio cell. In some implementations, the indicationis not sent to the UE 105 by the SV/sNB-DU 302 and instead support ofhigher layer protocol interaction with UE 105 (e.g. using PDCP, SDAP andRRC) is transferred from sNB-CU 307-1 to sNB-CU 307-2 with sNB-CU 307-2then instigating a reset or restart for one or more the higher layerprotocols and/or sending an indication (e.g. an RRC message) to UE 105indicating the transfer.

At stage 6, the SV/sNB-DU 301-1 buffers UL data received from the UE105. This stage may differ from a normal NR handover.

At stage 7, which differs from a normal NR handover for terrestrial gNBs114, the SV/sNB-DU 302 performs an F1 sNB-DU (or gNB-DU) removalprocedure to remove all signaling association with source sNB-CU 307-1,which occurs just prior to transfer of the SV/sNB-DU 302 to the newearth station ES2 and target sNB-CU 307-2.

At stage 8, which differs from a normal NR handover for terrestrial gNBs114, the SV/sNB-DU 302′ performs an F1 sNB-DU (or gNB-DU) setupprocedure, to establish a new signaling association with the targetsNB-CU 307-2, which occurs just after the transfer of the SV/sNB DU tothe new earth station and target sNB-CU 307-2.

In stages 9 and 10, the sNB-CU-UP 307-1UP and sNB-CU-CP 307-1CP performa bearer context modification procedure for the UE 105 (sNB-CU-CP307-1CP initiated) to enable the gNB-CU-CP 307-1CP to retrieve the PDCPUL/DL status for UE 105 and to exchange data forwarding information forthe bearer for UE 105.

At stage 11, the source gNB-CU-CP 307-1CP sends an SN STATUS TRANSFERmessage to the target gNB-CU-CP 307-2CP.

At stage 12, the SV/sNB-DU 302′ and target sNB-CU-CP 307-2CP perform anF1 UE context setup procedure for change of association of UE 105 to thetarget sNB-CU 307-2.

At stage 13, the target sNB-CU-CP 307-2CP sends a BEARER CONTEXTMODIFICATION REQUEST message containing address information for F1-U andPDCP status for UE 105.

At stage 14, the target sNB-CU-UP 307-2UP responds with a BEARER CONTEXTMODIFICATION RESPONSE message.

At stage 15, which may differ from a normal NR handover for terrestrialgNBs 114, the SV/sNB-DU 302′ resumes UL data transfer for UE 105.

At stage 16, data forwarding for UE 105 may be performed from the sourcegNB-CU-UP 307-1UP to the target gNB-CU-UP 307-2UP.

At stages 17-19, a Path Switch procedure is performed to update addressinformation for the NG-U interface for UE 105 towards the core network.

At stage 20, the target gNB-CU-CP 307-2CP sends an UE CONTEXT RELEASEmessage for UE 105 to the source gNB-CU-CP 307-1CP.

At stages 21 and 22, the source sNB-CU-UP 307-1UP and source sNB-CU-CP307-1CP perform a bearer context release procedure.

A regenerative SV, such as SV/sNB 202 or SV/sNB-DU 302, may avoid anychange and any significant interruption to radio cell UL or DL signalingby allowing each UE 105 to continue accessing a serving radio cell whenthe SV is transferred from one ES 104 to another ES 104, as describedpreviously. Therefore, UEs 105 may continue with the same radio cell, aslong as a serving 5GCN 110 is not changed. As discussed above, for aregenerative SV with a non-split architecture, such as SV/sNB 202, thecontinuation of a radio cell by a UE 105 with continuation of the same5GCN 110 results in control and L1/L2 impacts to the SV/sNB 202 and the5GCN 110. For a regenerative SV with split architecture, such asSV/sNB-DU 302, the continuation of a radio cell by a UE 105 withcontinuation of the same 5GCN 110 results in control and L1/L2 impactsto the SV/sNB-DU 302 and sNB-CU 307 if the sNB-CU 307 remains unchanged.A modified UE handover procedure may be used, as discussed above, thataffects the SV/sNB-DU 302, the sNB-CUs 307 and possibly the UE 105 butnot 5GCN 110 if the sNB-CU 307 is changed. The lack of any 5GCN 110impact for a regenerative SV with split architecture may be desirablefor an MNO, if an SVO owns and manages SVs and sNBs.

When there is a change of a radio cell following transfer of an SV102/202/302 from one ES 104 to another ES 104, UEs 105 previouslyaccessing the SV 102/202/302 may be offloaded gradually from theirprevious radio cells (e.g., a short time before the SV transfer) usingstandard UE handoff procedures. In some implementations, radio cells mayhave a lifetime of up to 5-15 minutes and, thus, the handoff operationscaused by SV and radio cell transfer may be relatively infrequentcompared to UE handoff due to movement of the radio cell itself whilesupported by the same earth station. For example for a moving radiocell, e.g., a radio cell produced without using a steerable SV antenna,the handoff interval may be in the range 6-140 seconds for LEO SVs,making a moving radio cell a predominate cause of handover.

FIG. 36B shows a signaling flow 3650 that shows a high level procedureto support UEs 105 which are accessing radio cells supported by an SV102/302 when the SV 102/302 is transferred from an ES1 104-1 to an ES2104-2 as in FIGS. 23 and 24 and FIGS. 32 and 33, where there may or maynot be a change of sNB 106 or sNB-CU 307. The procedure avoidsdisruption of signaling and data/voice transfer to these UEs.

In stages 1 a-1 d of FIG. 36B, at time T, user plane (UP) and controlplane (CP) signaling for UEs 105 is transported between a 5GCN 110 andeach UE 105 via the SV 102/302, ES1 104-1, and sNB1 106-1 or sNB-CU1307-1.

At stage 2 of FIG. 36B, prior to time T2, sNB1 106-1 or sNB-CU1 307-1initiates a handover of some or all UEs 105 to radio cells supported byother SVs. If all UEs 105 are handed over, stages 4-7 do not occur.

At stage 3, at time T2, the feeder link from ES1 104-1 to the SV 102/302is transferred to ES2 104-2.

At stage 4, if sNB1 106-1 or sNB-CU1 307-1 is not changed, UEs 105 nothanded over at stage 2 may be assisted to reacquire current servingradio cells. This may not be needed with regenerative SV mode with asplit architecture, e.g., as illustrated in FIG. 3, because the sNB-DU302 (which is part of the SV 302) may continue to support UE access atthe Layer 1, MAC and RLC levels.

At stage 5, if SV 102/302 control is moved from sNB1 106-1 or sNB-CU1307-1 to sNB2 106-2 or sNB-CU2 307-2, respectively, as part of thetransfer at stage 3, a handover procedure is used to transfer CP and UPsignaling links and sessions for UEs 105 not handed over at stage 2 fromsNB1 106-1 or sNB-CU1 307-1 to sNB2 106-2 or sNB-CU2 307-2,respectively. The handover procedure may be a subset of an existinghandover procedure in which UEs 105 are not required to access new radiocells. For example, the procedure shown in FIG. 36A may be used in thecase of an SV 302 transfer from sNB-CU1 307-1 to sNB-CU2 307-2. Becausean existing (or modified) procedure is used at stage 5, there may be nonew impact to the 5GCN 110. If transparent SV mode is used, e.g., asillustrated in FIG. 1, UEs 105 may also be assisted by sNB1/sNB-CU1106-1 to reacquire their current serving radio cells as part of stage 5,which may look to UEs 105 like a handover procedure to new radio cells.

At stages 6 a-6 d, when there is no change to sNB1/sNB-CU1 106-1/307-1,user plane (UP) and control plane (CP) signaling for UEs 105 stillaccessing the SV 102/302 is transported between the 5GCN 110 and each UE105 via the SV 102/302, ES2 104-2, and sNB1 106-1 or sNB-CU1 307-1.

At stages 7 a-7 d, when there is a change to sNB1/sNB-CU1 106-1/307-1,user plane (UP) and control plane (CP) signaling for UEs 105 stillaccessing the SV 102/302 is transported between the 5GCN 110 and each UE105 via the SV 102/302, ES2 104-2, and sNB2 106-2 or sNB-CU2 307-2.

Aspects of SOLUTION 3 to support and reuse existing 5G network accessprocedures with only small impacts are next discussed with reference toFIGS. 37 and 38.

The configuration of sNBs 106, 202 and 307 may occur during an initialsetup procedure. For example, information related to countries, PLMNs,fixed TAs and fixed cells that need to be supported by an sNB106/202/307 may be configured in the sNB 106/202/307 in advance usingO&M and/or by an attached 5GCN 110 during an NG Setup procedure when thesNB 106/202/307 is first connected to the 5GCN 110.

Initial access to a serving PLMN by a UE 105 may be efficientlysupported by a serving sNB 106/202/307. For example, an sNB 106/202/307may broadcast (e.g. using one or more SIBs) detailed information forsome or all fixed cells and/or some or all fixed TAs currently supportedby the sNB 106/202/307, or currently supported by a particular radiocell for the sNB 106/202/307, to enable a UE 105 to determine a fixedserving cell, a fixed serving TA and/or a serving PLMN before initiatingaccess to the serving PLMN. Broadcasting this type of detailedinformation, however, would consume SV bandwidth, add to latency and addextra impact to sNBs 106/202/307 and UEs 105. A more efficient solution,however, is for a serving sNB 106/202/307 to determine a UE 105'scountry and fixed serving cell and/or fixed serving TA at initial accessfrom a UE 105, based on a UE 105 provided or sNB 106/202/307 determinedlocation for the UE 105. Detailed information for fixed TAs within whichthe UE 105 is allowed to move (without triggering a new Registration)and constituent fixed cells for these TAs may then be provided to the UE105 by a serving AMF 122 at a NAS level.

In a connection management (CM) idle state, a UE 105 may periodicallyobtain its own location and may map the location to a fixed TA (e.g.using information for fixed TAs provided by a serving AMF 122 asdescribed above) to determine when to perform a new registration. If theUE 105 is in a CM connected state, the UE 105 may undergo intra-sNB orinter-sNB handover to change a radio cell, and possibly change an SV,due to mobility of the UE 105 and/or movement of the radio cell or theSV.

FIG. 37A shows a signaling flow 3700 that illustrates various messagessent between components of a communication network in a procedure forinitial PLMN access by a UE 105 to enable a UE 105 to access a PLMN isthe same country as the UE 105. The communication network may be part ofcommunication system 100, 200 or 300 for FIG. 1, 2 or 3, respectively,and is illustrated as including a UE 105, an SV 102/202/302, an sNB106/202/307, an AMF 122, and an LMF 124. It should be understood thatthe sNB 106/202/307 or an element of the sNB 106/202/307 may be includedwithin the SV 102/202/302. For example, with an SV 202, an sNB 202 wouldbe completely included within the SV 202 as described for FIG. 2.Alternatively, with an SV 302, an sNB 307 (also referred to as ansNB-CU) would be terrestrial and physically separate from the SV 302,but the SV 302 would include an sNB-DU 302 as described for FIG. 3.

At stage 1 in FIG. 37A, the UE 105 is in a 5G Mobility Management (5GMM)DEREGISTERED state and RRC IDLE state.

At stage 2, the UE 105 may detect radio cells from one or more radiobeams transmitted by one or more SVs, including the SV 102/202/302. ThesNB 106/202/307 may control SV 102/202/302 to broadcast systeminformation blocks (SIBs) in one or more radio cells of the sNB106/202/307. The SIBs may indicate one or more PLMNs (referred to assupported PLMNs) supported by the sNB 106/202/307 in each radio cell forthe sNB 106/202/307. The PLMNs may each be identified in a SIB by amobile country code (MCC) and a mobile network code (MNC), where the MCCindicates a country for each identified PLMN (i.e. a country to whicheach identified PLMN belongs—e.g. a country in which the PLMN is locatedor is allowed to operate).

At stage 3, which is optional, the UE 105 obtains location relatedmeasurements, e.g., for DL signals received from the SV 102/202/302,from other SVs 102/202/302, from gNBs 114 (not shown), from navigationSVs 190 (not shown), or from some combination of these.

At stage 4, which is optional, the UE 105 may receive location relatedinformation for the supported PLMNs broadcast (e.g. in one or more SIBs)in the one or more radio cells from the sNB 106/202/307 via the SV102/202/302. For example, the location related information for thesupported PLMNs may comprise geographic definitions for fixed cells ofeach supported PLMN, geographic definitions for fixed tracking areas ofeach supported PLMN, or both, and possibly geographic information for acountry or countries (e.g. information defining a border or borders ofone or more countries).

At stage 5, the UE 105 may optionally determine the location of the UE105 from the location related measurements from stage 3 if stage 3occurs. UE 105 may optionally determine the UE 105 country in which theUE 105 is located using the determined location and the location relatedinformation received at stage 4 if stage 4 occurs. In someimplementations, to assist country determination at stage 5, geographicinformation for a country or countries (e.g. information defining aborder or borders of one or more countries) may be pre-configured in aUE 105 or may be obtained by a UE 105 from a home PLMN at some previoustime.

At stage 6, UE 105 selects a radio cell. In one implementation, referredto as implementation 6, if the UE 105 did not determine the UE 105country at stage 5, the UE 105 may first select a PLMN (referred to as apreferred PLMN), where the PLMN is a preferred PLMN in the supportedPLMNs indicated at stage 2 in the one or more radio cells of the sNB106/202/307. The UE 105 may then select the radio cell at stage 6 basedon the radio cell indicating support for the preferred PLMN. In anotherimplementation, referred to as implementation I7, if the UE 105 diddetermine the UE 105 country at stage 5, the UE 105 may first select aPLMN (referred to as the selected PLMN), where the PLMN is in thesupported PLMNs indicated at stage 2 in the one or more radio cells ofthe sNB 106/202/307 and belongs to the UE 105 country. The selected PLMNmay also be a preferred PLMN for UE 105. The UE 105 may then select theradio cell at stage 6 based on the radio cell indicating support for theselected PLMN.

At stage 7, UE 105 may send to the sNB 106/202/307 via the SV102/202/302 and using the selected radio cell an RRC Setup Requestmessage (e.g. after having performed a random access procedure to obtaininitial access to the selected radio cell). If the location and/orcountry of the UE 105 is obtained at stage 5, the UE may include thelocation and/or country in the RRC Setup Request message.

At stage 8, if the location and country are not included at stage 7(e.g. with implementation I6), sNB 106/202/307 may determine a locationfor UE 105, e.g., from a beam coverage area of the selected radio cellto approximate the UE 105 location. The beam coverage area, for example,may be inferred from a known location of the SV 102/202/302 and a beamdirection and angular range. The sNB 106 may further determine the UE105 country, e.g., based on the UE 105 location. In someimplementations, the location determination and location mapping to acountry may be performed by a Location Management Component (LMC) whichmay be part of, attached to, or reachable from, sNB 106/202/307. Atstage 8, if the location and/or country are included at stage 7 (e.g.with implementation I7), sNB 106/202/307 may determine and/or verify thelocation and country for UE 105 in a manner similar to that describedfor the determination of the location and country. The sNB 106/202/307may then determine whether the country of the UE 105 (e.g. as receivedat stage 7 and/or determined or verified at stage 8) is supported by thesNB 106/202/307.

At stage 9, the sNB 106/202/307 may return an RRC Reject to UE 105 ifthe country of UE 105 is not supported. The RRC Reject may indicate thecountry (e.g. using an MCC) that the UE 105 is located in. If an RRCReject is received, the UE 105 may restart at stage 6 using the providedcountry (or may first verify the provided country as at stage 5 and thenrestart at stage 6).

At stage 10, the sNB 106/202/307 may return an RRC Setup carrying anindication of the country (e.g. where the indication is an MCC), e.g.,if the sNB 106/202/307 verified or determined the country at stage 8.

At stage 11, if a country is received at stage 10, the UE 105 selects asupported PLMN (referred to below as the selected PLMN) for the providedcountry. The selected PLMN may be one the supported PLMNs indicated atstage 2 in the one or more radio cells of the sNB 106/202/307 andbelongs to the UE 105 country. Alternatively, the selected PLMN may beselected as a supported PLMN for a radio cell of a different sNB106/202/307 (referred to below as “the sNB 106/202/307”) and belongs tothe UE 105 country. The selected PLMN may also be a preferred PLMN forUE 105. If a country is not received at stage 10 or is received at stage10 and is the same as a country determined at stage 5 (e.g. withimplementation I7), UE 105 may continue to use a PLMN selected at stage6 as the selected PLMN (i.e. where the selected PLMN belongs to thecountry of the UE 105). The selected PLMN is also referred to as aserving PLMN below since the selected PLMN acts as a serving PLMN for UE105 following stage 18.

At stage 12, UE 105 sends an RRC Setup Complete to the sNB 106/202/307and includes an indication (e.g. MCC and MNC) of the selected PLMN and aNon-Access Stratum (NAS) Registration Request message. UE 106 may alsoinclude a location of UE 105, e.g. as determined at stage 5, if UE 105selects the selected PLMN for a radio cell of a different sNB106/202/307 at stage 11.

At stage 13, the sNB 106/202/307, or an embedded or attached LMC, maydetermine a fixed serving cell and/or a fixed serving TA for UE 105,e.g., by mapping a UE 105 location that was received at stage 7 or stage12 or verified or determined at stage 8, to a Cell ID and/or TAC, forthe selected PLMN indicated at stage 12.

At stage 14, the sNB 106/202/307 forwards the NAS Registration Requestwith an indication of the fixed serving cell and/or fixed serving TA ifdetermined at stage 13 (e.g., the Cell ID and TAC) to an AMF 122, e.g.,in an NG Application Protocol (NGAP) Initial UE message. In someimplementations, the AMF 122 or LMF 124 may perform the fixed celland/or fixed TA (Cell ID and/or TAC) determination (and possiblylocation of the UE 105), in which case the NAS Registration Request orNGAP Initial UE message may include a UE location or UE locationinformation instead of the Cell ID and TAC at stage 14.

At stage 15, the AMF 122 may send a request for the fixed cell and/orfixed TA (Cell ID and/or TAC) for the selected PLMN to the LMF 124 ifthe sNB 106/202/307 did not determine the Cell ID and TAC in stage 13.

At stage 16, the LMF 124 may provide the AMF 122 with the fixed celland/or fixed TA (Cell ID and/or TAC) for the selected PLMN.

At stage 17, the AMF 122 may map the location of the UE 105 to anidentity of the fixed serving cell and/or an identity of the fixed TA,if not performed by the sNB 106/202/307 or the LMF 124. At stage 17, theAMF 122 also determines allowed TAs (TACs) for the UE 105 in theselected PLMN, where the UE 105 is allowed to access the selected PLMNin each TA of the allowed TAs without needing to perform anotherRegistration with the selected PLMN. AMF 122 may perform other actionsat stage 17 associated with Registration of a UE 105 such asauthenticating the UE 105 and registering the UE 105 in a home UnifiedData Management (UDM) (not shown) and UE 105 and AMF 122 may performadditional actions associated with an initial registration after stage19 which are not shown here but are well known in the art.

At stage 18, the AMF 122 returns a NAS Registration Accept message to UE105 via sNB 106/202/307 that includes the allowed fixed TAs (referred tohere as TAs) (TACs) and location information such as geographicdefinitions of the allowed TAs and constituent fixed cells for theallowed TAs. For example, the geographic definitions of the allowed TAsand constituent fixed cells may be defined using grid points and/orpolygons as described above for SOLUTION 1. A Registration flag may alsobe included in the NAS Registration Accept message to indicate if the UE105 is or is not required to perform a registration with the servingPLMN for a change of TA after detecting that the UE 105 is no longer inany of the allowed TAs.

At stage 19, the UE 105 stores the allowed TAs, the geographicdefinitions of the allowed TAs and constituent fixed cells and theRegistration flag (if included) to allow later determination of acurrent TA and current fixed cell.

As part of stage 19, UE 105 may access the serving PLMN to obtain orenable various services. For example, UE 105 may: (i) determine acurrent location of the UE 105 (e.g. as at stages 3 and 5); (ii) map thecurrent location to one of the allowed TAs stored at stage 19 and/or toone of the constituent fixed cells for an allowed TA based on thegeographic definitions of the allowed TAs and/or constituent fixedcells; and (iii) include an indication of the allowed TA and/or anindication of the constituent fixed cell in a message sent to theserving PLMN. For example. the indication of the allowed TA, theindication of the constituent fixed cell or both may enable a servicefor the UE or by the serving PLMN. As an example, the message may be aSession Initiation Protocol (SIP) INVITE message sent to establish anemergency call for the UE 105 and the indication of the constituentfixed cell may correspond to a fixed serving cell for the UE 105 and theservice may comprise routing the SIP INVITE message to a PSAP to helpestablish the emergency call. Alternatively, the message may be a SIP orNAS message and the service may comprise provision of lawfulinterception (LI) in which information for the UE 105 is sent to an LIclient.

At stage 20 in FIG. 37A, which may occur some time period after stage 19(e.g. a few seconds to an hour or more later), the UE 105 may determineif registration is required for a change of TA. For example, the UE 105may detect one or more new radio cells (e.g. each comprising one or moreradio beams) from one or more SVs that are different than SV102/202/302, where each of the new radio cells indicates support for theserving PLMN. The UE 105 may receive an indication of supported TAs(e.g. TACs) of the serving PLMN broadcast (e.g., in SIBs) in the newradio cells. The UE 105 may determine that registration is required withthe serving PLMN for a change of TA, based at least in part on theallowed TAs stored at stage 19 and the supported TAs indicated at stage20. For example, registration may always be required with the servingPLMN for a change of TA if the TAs supported by the new radio cells donot include any TA in the allowed TAs received at stage 18 and stored instage 19. Conversely, registration may not be required for someconditions C1 if the supported TAs supported by the new radio cellsinclude at least one of the allowed TAs received at stage 18 and storedin stage 19 and that is supported by one or more of the new radio cells.As an example of the conditions C1, registration may not be required ifthe NAS Registration Accept message from stage 18 includes an indication(e.g. the Registration flag) allowing the UE 105 to access the servingPLMN using a radio cell supporting at least one of the allowed TAs whenthe UE is not located in any of the allowed TAs. In anotherimplementation, the UE 105 may determine if registration is required bydetermining a current location of the UE 105 and determining whether thecurrent location of the UE is inside any allowed TA received at stage 18and stored in stage 19. Registration may be required (e.g. whenconditions C1 do not apply) when the current location of the UE 105 isnot inside any allowed TA or when the current location of the UE isinside an allowed TA but the allowed TA is not included in the TAssupported by the new radio cells. Conversely, registration may not berequired when the current location of the UE is inside an allowed TA andthe allowed TA is included in the TAs supported by the new radio cells.Registration may additionally be required, e.g., if the NAS RegistrationAccept message at stage 18 includes an indication (e.g. the Registrationflag) requiring the UE to perform registration for a change of TA withthe serving PLMN when the UE is not located inside any of the allowedTAs.

At stage 21 which is conditional, a NAS registration request for thechange of TA may be transmitted to the AMF 122 by the UE 105 using oneof the new radio cells from a different SV when the UE determines the UE105 is required to perform the registration with the serving PLMN forthe change of TA. In some implementations, the UE 105 may camp on theone of the new radio cells without performing the registration with theserving AMF 122 for the change of TA, e.g., when the UE 105 is in anidle state and when the UE 105 determines that registration is notrequired. The UE may access the serving AMF 122 using one of the newradio cells without performing the registration with the serving AMF 122for the change of TA, when the UE is in a connected state and when theUE determines that registration is not required.

At stage 22 which is conditional, a NAS Registration Accept may bereturned by the AMF 122 to UE 105 if the Registration Request wastransmitted in stage 21.

FIG. 37B shows a signaling flow 3750 that illustrates various messagessent between components of a communication network in a procedure forinitial PLMN access by a UE 105 to enable a UE 105 to access a PLMN isthe same country as the UE 105. Signaling flow 3750 is a variant ofsignaling flow 3700 for FIG. 37A in which UE 105 location informationcan be more protected and some RRC message impacts may be reduced oravoided. As discussed above, it is normally required that when a UEinitially accesses a PLMN that the PLMN is in the same country as theUE. The procedure illustrated in FIG. 37B is based on existing PLMNinitial access procedures as described in Third Generation PartnershipProject (3GPP) Technical Specification (TS) 38.300 and 3GPP TS 23.502.The main differences are use of a UE location capability to provide acurrent UE location to an sNB or sNB-CU 106/202/307 and an ability of ansNB or sNB-CU 106/202/307 to determine whether the UE 105 location isinside the country supported by the sNB or sNB-CU 106/202/307.

At stage 1 of FIG. 37B, the UE 105 starts off in EMM-DEREGISTERED andRRC IDLE states.

At stage 2, the sNB or sNB-CU 106/202/307 broadcasts (via an SV102/202/302) an indication of supported PLMNs (e.g. MCC-MNC) in eachradio cell. The sNB or sNB-CU 106/202/307 may also indicate in a SIBwhether a UE 105 location will be needed at stage 8 (or may provideconditions for inclusion of a UE 105 location at stage 8 such as forinitial PLMN access) and may include security information describedbelow for stage 6 such as public key(s) and an indication of cipheringalgorithm(s). For example, for a radio cell well inside the interior ofa country, UE 105 location may not be requested unless needed todetermine a fixed TA and fixed serving cell (e.g. at stage 9). Anindication of location requirement at stage 2 may provide more time fora UE 105 to obtain a location than an indication at stage 6.

At stage 3, the UE 105 determines the UE 105 location (e.g. via GNSS) ifthe UE 105 is location capable and may determine the correspondingcountry. Performing this stage may continue if needed up until stage 8.

At stage 4, the UE 105 selects a radio cell (and an associated SV102/202/302) which supports a preferred PLMN and the UE country ifalready known (e.g., if determined at stage 3).

At stage 5, the UE 105 sends an RRC Setup Request to an sNB or sNB-CU106/202/307 supporting the radio cell selected at stage 4 to request anRRC signaling connection. The UE 105 may include a confidential location(also referred to as a ciphered location or concealed location) at stage5 if the RRC Setup Request may be extended. This could reduce signalingin the case that the UE 105 is not in the correct country, although itcould also require broadcasting all of the security information at stage2.

At stage 6, the sNB or sNB-CU 106/202/307 returns an RRC Setup message.If the radio cell being accessed by the UE 105 has a coverage area whichspans more than one country (e.g. crosses an international border) or ifa UE 105 location is needed to determine a fixed TA and fixed servingcell for the UE, the sNB or sNB-CU 106/202/307 includes a request forthe location of the UE 105 and provides security information if notprovided at stage 2 that may include a public ciphering key and anindication of a ciphering algorithm.

At stage 7, the UE 105 selects a preferred PLMN from among the PLMNsindicated at stage 2. If PLMNs for only one country are indicated atstage 2, UE 105 could assume that it is in the same country as thesePLMNs and could select one of these PLMNs as the preferred PLMN.Alternatively, if UE 105 determines a country at stage 3, UE 105 mayselect a preferred PLMN at stage 7 that is either in the countrydetermined at stage 3 or allowed to serve the country determined atstage 3.

At stage 8, the UE 105 sends an RRC Setup Complete message indicatingthe selected PLMN and including a NAS Registration Request. If locationwas requested at stage 6 or indicated at stage 2, the UE 105 may includethe location determined at stage 3. The location may be included in aconfidential form by ciphering, e.g. using a public ciphering key andciphering algorithm indicated at stage 2 or stage 6. The determinationand encoding of the confidential location may reuse some of thefunctionality used to support a Subscription Concealed Identifier (SUCI)as described in 3GPP TS 23.003.

At stage 9, if a location was requested (at stage 2 or stage 6) andincluded at stage 8, the sNB or sNB-CU 106/202/307 deciphers theconfidential location received at stage 8, e.g. using a private key(corresponding to the public key used by the UE 105). If countryverification is needed, the sNB or sNB-CU 106/202/307 maps the locationto a country and verifies the country is supported by the sNB or sNB-CU106/202/307 and matches the country for the selected PLMN. The sNB orsNB-CU 106/202/307 may also or instead map the UE location to a Cell ID(for a fixed cell) and/or TAI (for a fixed TA) for the selected PLMN(e.g. if the sNB or sNB-CU 106/202/307 has been configured with fixedcell and fixed TA information). When a UE 105 location is not providedat stage 8, the sNB or sNB-CU 106/202/307 may use the radio cellcoverage area for the UE 105 as an approximate location (e.g. in orderto determine a fixed TA or to forward a location at stage 10).

At stage 10, if the UE country determined at stage 9 is not supported bythe sNB or sNB-CU 106/202/307 (or does not march the country for theselected PLMN), the sNB or sNB-CU 106/202/307 returns an RRC Release tothe UE 105 and includes the country determined at stage 9 and/or anindication that the PLMN selected for stage 9 does not match the countryof the UE 105. The UE 105 may then restart PLMN selection at eitherstage 3 (e.g. in order to verify the UE 105 country) or stage 4.

At stage 11, if the UE 105 is in the correct country, the sNB or sNB-CU106/202/307 forwards the Registration Request to an AMF 122 for theselected PLMN and includes the Cell ID and/or TAI if obtained at stage 9or the location obtained at stage 9 otherwise.

At stage 12, if no Cell ID and TAI were included at stage 11, the AMF122 (or an associated LMF 124) determines a cell ID and/or TAI (for afixed cell and/or fixed TA) from the location received at stage 11.

At stage 13, the AMF 122 returns one or more allowed TAIs to the UE 105and geographic definitions of the associated fixed TAs and/orconstituent fixed cells for the associated fixed TAs (e.g. using gridpoints). A Registration flag may also be included to indicate if the UEis required to perform a registration for a change of TA. Registrationfor a change of TA may be referred to as “location tracking” because UE105 can then be required to track its location in order to determinewhen a change of TA has occurred. With location tracking, a UE 105 mayperiodically map its current location to a fixed TA based on the fixedTA geographic definitions received at stage 13 and to perform a newregistration if no longer within an allowed TA. Without locationtracking, a UE 105 need not determine a current TA periodically and mayassume presence in an allowed TA so long as the UE 105 can access aradio cell that supports at least one allowed TA. This option enablesthe AMF 122 to page the UE 105 (via an allowed TA) even when the UE 105moves out of an allowed TA and reduces the amount of location supportneeded from the UE 105. For a UE 105 which is not location capable, thegeographic definitions of the fixed TAs and constituent fixed cellswould not need to be provided by the AMF 122 at stage 13.

At stage 14, the UE 105 stores the fixed TA and/or fixed cell geographicdefinitions (if provided) to allow later determination of a currentfixed TA and current fixed serving cell (e.g. to enable registration ina new TA and regulatory services dependent on a current serving cell).

In CM IDLE and RRC IDLE states, a UE 105 may select and camp on anysuitable radio cell which indicates support for an allowed TA for theregistered PLMN. Selection of a new radio cell for a different SV and/ordifferent sNB or sNB-CU 106/202/307 may occur (e.g. when coverage by aprevious radio cell starts to disappear) so long as the new radio cellsupports an allowed TA.

Paging may operate as for a terrestrial NR access, with an AMF 122sending a paging message to one or more sNBs 106/202 (or sNB-CUs 307)which broadcast the paging message over all radio cells which supportthe fixed TAs allowed for the UE 105.

If location tracking is not required (see stage 13 in FIG. 37B), a UE105 may continue to access a radio cell for a serving PLMN whichadvertises support for at least one allowed fixed TA for the UE 105.

If location tracking is required (see step 13 of FIG. 37B), a locationcapable UE 105 periodically obtains a current UE location and verifiespresence in an allowed fixed TA. As described above, TA boundaries maybe precisely aligned with the border of a country or may simply bedefined within a country to ensure that when a UE 105 verifies beinginside an allowed TA, the UE 105 is also located inside the associatedcountry.

If the UE 105 is no longer in an allowed TA (and therefore possibly nolonger in a previous country) or cannot access a radio cell supportingan allowed TA, the UE 105 performs a new registration, which may use thesame procedure as in FIG. 37A or FIG. 37B or a subset of this procedure.

Support for a UE 105 without location capability may be possible, e.g.as described for stage 8 in FIG. 37A. For example, a current radio beamcoverage area for a UE 105 may be used by an sNB 106/202/307 todetermine a UE 105 country and a fixed serving TA. While support forlocation of a UE 105 using a current radio beam coverage area may notalways be reliable, there are alternatives that may be used to avoid orreduce erroneous outcomes. In one implementation, a radio beam coveragearea may be directed by an SV 102/202/302 (e.g. using a steerableantenna array) primarily within one country with either zero or lowcoverage of adjacent countries. A UE 105 able to access a radio cellusing such a radio beam may then be assumed to be within the countryassociated with the radio beam (or associated with the radio cell if allradio beams for the radio cell are directed into the same country). Thisimplementation may be suitable for regions, such as the European Unionwith common regulations. In another implementation, a UE 105 with nolocation capability may be prohibited from accessing a radio cell whosecoverage area spans more than one PLMN or more than one country, whichmay be suitable, e.g., in large countries except near borders. Forexample, a flag may be broadcast by an sNB 106/202/307 (e.g. using aSIB) within each radio cell supported by the sNB 106/202/307. The flagmay indicate whether a UE 105 without a location capability is allowedto access a PLMN associated with the radio cell. If the flag indicatesthat access is not allowed, a UE 105 without a location capability mayrefrain from initial access to the associated PLMN, though possibly maybe allowed to access the PLMN if already registered with the PLMN. Theflag may be set to indicate that access is not allowed when the radiocell has a coverage area spanning more than one country or more than onePLMN coverage area.

In another implementation, a UE 105 may periodically interact with ansNB 106/202/302 or an AMF 122 to obtain or verify the UE 105 locationand current fixed serving TA. A RAN procedure may be used when the UE isin CM Idle state or periodic Registration may be enhanced for AMF 122 orLMF 124 determination. This implementation may reduce the likelihood oferrors, but at the expense of more signaling by a UE 105 and PLMN.

When a UE 105 is in or has just entered a CM idle state, the UE 105 mayselect and then camp on a suitable or acceptable radio cell. Forexample, the UE 105 may be aware of allowed TAs following the latestRegistration of the UE 105 in which allowed TAs are indicated to the UE105, e.g. as described for stage 18 of FIG. 37A. The UE 105 may thenselect and camp on a suitable radio cell that indicates support for anallowed TA for the serving (and registered) PLMN. Selection of a newradio cell (e.g. for a different SV 102/202/302 and/or different sNB106/202/307) may occur so long as the radio cell supports an allowed TAas previously indicated by the serving PLMN. A radio cell for a LEO orMEO SV may broadcast information (e.g. carrier frequency and beamangles) for other radio cells whose coverage areas will later move intothe current coverage area of the radio cell. This may assist a UE 105that is currently accessing or camping on the radio cell to find andaccess a new radio cell (e.g. one of the other radio cells) after thecoverage area of the radio cell has moved away from the current UE 105location. Paging of a UE 105 may operate as for terrestrial NRaccess—e.g. with an AMF 122 sending a paging message to one or more sNBs106/202/307, which each sNB 106/202/307 broadcasting the paging messageover all radio cells controlled by the sNB 106/202/307 that support anyof the TAs allowed for the UE 105.

As discussed in stages 20-22 for FIG. 37A, registration may be performedby a UE 105 for a change of allowed TA. A UE 105 with a locationcapability, for example, may periodically determine its current locationand maps the location to a fixed TA. If the registration flag discussedfor stages 18 and 20 of FIG. 37A indicates registration is required fora change of TA, the UE 105 may perform a new registration afterdetecting that the UE 105 is no longer located inside an allowed TA. Ifthe Registration flag indicates that registration is not required for achange of TA, the UE 105 may not be required to perform a Registrationafter detecting that it is no longer inside an allowed TA, e.g., as longas the UE 105 remains camped on a radio cell that supports an allowedTA. In this case, for example, the UE 105 may perform a registrationwhen no suitable radio cell is found for any allowed TA. Registrationfor a change of TA, for example, may not be used when the current UE 105location is distant from a country or PLMN border. The Registration fora change of TA may operate similarly to Registration for initial PLMNaccess (e.g. as described for stages 21 and 22 of FIG. 37A) except thatthe radio cell selected by the UE 105, e.g., at stage 20 of FIG. 37A,needs to support the current serving PLMN.

As discussed above, a UE 105 access to a core network, e.g., 5GCN 110,via an SV 102/202/302 may require UE 105 handovers to new SVs102/202/302 and SV 102/202/302 transfers or handovers to new earthstations 104. For example, a LEO SV 102/202/302 may be accessible from afixed ground location for around 2 to 15 minutes, depending on theheight of the SV 102/202/302 and the perpendicular distance (measuredover the Earth's surface) between the fixed location and the orbitalplane of the SV 102/202/302. Following a period of accessibility to anSV 102/202/302 by a UE 105, a UE 105 accessing the SV 102/202/302, orsimply camped on a radio cell for the SV 102/202/302, may be required tohandover to another SV 102/202/302 or to camp on a radio cell foranother SV 102/202/302, respectively. Similarly, following a period ofaccessibility by an SV 102/202/302 to an earth station 104, the SV102/202/302 itself and any UEs 105 still accessing the SV 102/202/302may be required to undergo handover (or transfer) to another earthstation 104. Further, after the transfer of the SV 102/202/302 toanother earth station 104, characteristics of each radio cell supportedby the SV 102/202/302, including a coverage area and radio cell ID, maychange. In addition, a radio cell for an SV 102/202/302 may move (e.g.continuously or at discrete intervals), e.g., if the SV 102/202/302 doesnot include a steerable directional antenna, and accordingly may supporta particular fixed TA for only part of a time interval during which theSV 102/202/302 is accessing the same earth station 104. From theperspective of a UE 105, these handover and transfer events may besudden and disruptive to communication, e.g., if a new SV 102/202/302cannot be found before the UE 105 needs to cease access to a current SV102/202/302. In addition, from a network perspective, the handover of alarge numbers of UEs 105 from one SV 102/202/302 to another at about thesame time may impose an unacceptable system load.

In one implementation, based on knowledge of future orbital locations ofan SV 102/202/302, a duration of radio coverage by the SV 102/202/302for any location on the Earth and a duration of accessibility to the SV102/202/302 by any earth station 104 may be determined in advance (e.g.by an O&M server). For example, the determination of the duration ofradio coverage by the SV 102/202/302 for any location may take intoaccount the radio cells supported by the SV 102/202/302 including thecoverage areas of these radio cells and whether steerable directionalantennas are used to maintain coverage for the same geographic area by aradio cell over an extended period. Similarly, the determination of theduration of accessibility to the SV 102/202/302 by an earth station 104may take into account the orbit and the orbital positions of the SV102/202/302 and the position of the ES 104 relative to this orbit. Withthis information, it may be possible to determine: 1) a period of time(e.g. start time and end time) during which an SV 102/202/302 will beaccessing a particular earth station 104; and 2) a period of time (e.g.start time and end time) during which a particular radio cell for an SV102/202/302 will be providing radio coverage for part or all of thegeographic area of a given fixed TA. Information related to the timeduring which an SV 102/202/302 will access a particular earth station104 and/or the time during which a particular radio cell for an SV102/202/302 will provide radio coverage to a current location of a UE105 may be provided to a UE 105 accessing or camped on the SV102/202/302.

For example, in instances where all UEs 105 will be handed off from acurrent SV 102/202/302 to a new (different) SV 102/202/302, the UEs 105may be provided with an advance indication of the impending handoverbased on a period of time during which an SV 102/202/302 will beaccessing a particular earth station 104. Similarly, the UEs 105 may beprovided with an advance indication that radio cell coverage of anyfixed TA by the SV 102/202/302 will cease at some imminent future timebased on a period of time during which a particular radio cell for theSV 102/202/302 will be providing radio coverage for part or all of thefixed TA. With this information, the UEs 104 may find another SV102/202/302, before coverage from the SV 102/202/302 ceases.

A duration of radio coverage by a particular radio cell for a currentcoverage area of the radio cell may be referred to as a “lifetime of theradio cell”, and a remaining duration of the radio coverage (at anyparticular time during the radio coverage) may be referred to as a“remaining lifetime of the radio cell”. Similarly, a duration of radiocoverage by a particular radio cell for part or all of a geographic areaof a particular fixed TA may be referred to as a “lifetime of the radiocell for support of the TA” or as a “lifetime of the TA”, and aremaining duration of the radio coverage (at any particular time duringthe radio coverage) may be referred to as a “remaining lifetime of theradio cell for support of the TA” or as a “remaining lifetime of theTA”.

In one implementation, to avoid UEs 105 camping on or continuing toaccess a radio cell whose lifetime is nearly complete or whose lifetimefor support of some TAs is almost complete, an SV 102/202/302 mayprovide advance indication(s) to UEs 105 that are accessing the radiocell of a remaining lifetime for the radio cell and/or a remaininglifetime for the radio cell for support of each of one or more TAs. Insome implementations, the advance indication(s) may be provided usingSystem Information Blocks (SIBs) such as SIB1 or SIB2. For example, aSIB1 or SIB2 for a particular radio cell supported by an SV 102/202/302may include parameters such as: the remaining lifetime of the radio cell(e.g. 0-1023 seconds or 0-255 seconds); a list of TAs supported by theradio cell; and for each supported TA, the remaining lifetime of theradio cell for each supported TA; or a combination thereof.

After receiving an indication of the remaining lifetime of the radiocell and/or the remaining lifetime of the radio cell for each supportedTA, a UE 105 in idle state may start to look for another radio cellsupporting an allowed TA some time before the remaining lifetime of theradio cell and/or the remaining lifetime(s) of the radio cell forallowed TA(s) will expire. Similarly, a UE in connected state mayprepare for handover by looking for and obtaining measurements for otherradio cells before the remaining lifetime of the radio cell and/or theremaining lifetime(s) of the radio cell for allowed TA(s) will expire.

Radio cells may also broadcast information to help a UE 105 acquire anew radio cell (e.g. from another SV 102/202/302) whose radio coveragewill move into an area supported by a current radio cell for the UE 105.Such new radio cells might not be detected by a UE 105 in advancebecause their radio coverage might not yet support the current locationof the UE 105. However, if a UE 105 knows when a coverage of a new radiocell will start (e.g. by being provided with a list of new radio cellsthat will support or partially support a particular fixed TA and thetimes at which the coverages will start), the UE 105 may attempt toacquire one of these new radio cells after a coverage is expected tostart.

FIG. 38 shows a signaling flow 3800 that illustrates various messagessent between components of a communication network in a procedure forproviding an indication of a remaining lifetime of a current radio cell(e.g. for support of a fixed TA), as discussed above. The communicationnetwork may be part of communication system 100, 200 or 300 for FIG. 1,2 or 3, respectively, and is illustrated as including a UE 105, a firstSV1 102/202/302-1 and a second SV2 102/202/302-2 (sometimes collectivelyreferred to as SVs 102/202/302), an sNB 106/202/307, and an AMF 122. TheSVs 102/202/302 may be used in a transparent mode (e.g. may be SVs 106),a regenerative mode with a non-split architecture (e.g. may be SVs 202)or in a regenerative mode with a split architecture (e.g. may be SVs302), e.g., as discussed in FIGS. 1-3. For example, the sNB 106/202/307may be terrestrial (e.g., may be an sNB 106 in FIG. 1) when the SVs102/202/302 are used in the transparent mode. The sNB 106/202/307 may bepart of each SV 102/202/302 when the SVs 102/202/302 are used in theregenerative mode with the non-split architecture, as illustrated inFIG. 2, in which case there would be two sNBs 202 each part of one ofthe SVs 102/202/302. The sNB 106/202/307 may be terrestrial and maycomprise an sNB-CU 307, as discussed for sNB-CU 307 in FIG. 3, when theSVs 102/202/302 are used in the regenerative mode with the splitarchitecture.

At stage 1 in FIG. 38, the AMF 122 for a serving PLMN for UE 105 mayprovide the UE 105 with a NAS Registration Accept message with one ormore allowed TAs (TACs) for the serving PLMN, e.g., as discussed instage 18 of FIG. 37A and for stage 13 of FIG. 37B. The NAS RegistrationAccept message, for example, may optionally include an indication thatthe UE 105 may access the serving PLMN via a radio cell supporting anallowed TA for the UE 105 when the UE 105 is not located in an allowedTA.

At stage 2, the sNB 106/202/307 may provide the UE 105 via the SV1102/202/302-1 with a broadcast system information block (SIB) indicatingsupported PLMNs for a first radio cell for the sNB 106/202/307 to whichthe UE 105 is connected (or camped on) and supported TAs for eachsupported PLMN.

At stage 3, the UE 105 may access the serving PLMN via the SV1102/202/302-1, sNB 106/202/307, and AMF 122, based on the allowed TAsvia the first radio cell. For example, the UE 105 may determine whetherthe UE 105 is located inside an allowed TA and determine whether thefirst radio cell supports the serving PLMN and the allowed TA. The UE105 may access the serving PLMN via the first SV1 102/202/302-1 and thefirst radio cell for the first SV1 102/202/302-1 when the UE 105determines the UE 105 is located inside the allowed TA and the UE 105determines the first radio cell supports the serving PLMN and theallowed TA. In another example, the UE 105 may determine whether thefirst radio cell supports the serving PLMN and an allowed TA and mayreceive an indication that the UE 105 may access the serving PLMN whenthe UE 105 is not located in an allowed TA, e.g., as discussed at stage1. The UE 105 may access the serving PLMN via the first SV1102/202/302-1 and the first radio cell when the UE 105 determines theserving PLMN and an allowed TA are supported by the first radio cell(e.g. and when the UE is either located inside an allowed TA or notlocated inside an allowed TA).

At stage 4, the sNB 106/202/307 may determine one or more TAs (assumedto be fixed) supported by the first radio cell. The one or more TAs maybelong to a plurality of PLMNs supported by the first radio cell. Forexample, the sNB 106/202/302 may determine TAs currently supported bythe first radio cell based on TAs with geographic areas overlapping witha coverage area of the first radio cell, where the overlap between thegeographic area of each TA of the TAs and the coverage area of the firstradio cell satisfies one or more predetermined criteria for each TA. Foreach TA, the criteria, for example, may include inclusion of thegeographic area of the TA within the coverage area of the first radiocell, inclusion of the coverage area of the first radio cell within thegeographic area of the TA, an overlap of the coverage area of the firstradio cell with the geographic area of the TA that exceeds apredetermined threshold, or some combination of these, e.g. as discussedfor FIG. 6.

At stage 5, the sNB 106/202/307 may determine a remaining lifetime forthe first radio cell, e.g., an amount of time until there is a change ofthe first radio cell. The change of the first radio cell may include,for example: a change of an earth station 104 used by the sNB106/202/307 to exchange signaling for the first radio cell either withthe SV1 for the first radio cell when SV1 comprises an SV 102 or 302 orwith a 5G core network (e.g. AMF 122 in a 5GCN 110) when SV1 comprisesan SV 202 (and thus also includes the sNB 202); a change in timing forthe first radio cell; a change in carrier frequency for the first radiocell; a change in bandwidth for the first radio cell; a change incoverage area for the first radio cell; a change to radio beams used bythe first radio cell; a change in a cell identity for the first radiocell; a cessation of support by the first radio cell for one or more TAsbelonging to one or more PLMNs supported by the first radio cell; atermination of support for the first radio cell by the sNB 106/202/307;or any combination of these. The sNB 106/202/307 may also or insteaddetermining a remaining lifetime for each TA in the one or more TAssupported by the radio cell as determined at stage 4, where theremaining lifetime for each TA is an amount of time until the radio cellceases support for that TA. For example, the radio cell may beconsidered to cease support for any TA when the overlap between thegeographic area of that TA and the coverage area of the radio cell nolonger satisfies the particular criteria for that TA discussed for stage4.

At stage 5, the sNB 106/202/307 may use knowledge of the future (e.g.orbital) locations of the SV1 102/202/302-1 to determine the duration ofradio coverage of the first radio cell, e.g., based on the coverage areaof the first radio cell and whether SV1 102/202/302-1 includes asteerable directional antenna to maintain coverage for a same geographicarea. The sNB 106/202/307 may accordingly determine a period of time(e.g. start time and end time) during which the SV1 102/202/302-1 willbe using a particular earth station 104 (not shown) and/or a period oftime (e.g. start time and end time) during which the first radio cellwill be providing radio coverage for part or all of a TA. The sNB106/202/307 may use this information to determine the remaining lifetimefor the first radio cell and/or the remaining lifetime of each TA.

At stage 6, the sNB 106/202/307 generates a SIB, e.g., a SIB type 1(SIB1) or a SIB type 2 (SIB2), and includes the remaining lifetime forthe first radio cell and/or the remaining lifetimes for TAs supported bythe first radio cell and broadcasts the SIB to the UE 105 via the SV1102/202/302-1. For example, the remaining lifetime for the first radiocell may indicate an interval a time until a change in the first radiocell will occur, and/or may include an interval of time for each TA in aplurality of TAs supported by the first radio cell indicating when eachTA will no longer be supported by the radio cell.

At stage 7, the UE 105 may determine when to perform a cell change or ahandover from the first radio cell to a different radio cell and toaccess the serving PLMN via a SV2 102/202/302-2 using a different radiocell based on the remaining lifetime for the first radio cell and/or theremaining lifetimes of one or more TAs received at stage 6. For example,the UE 105 may begin the cell change or handover process a predeterminedtime before the expiration of the remaining lifetime for the first radiocell and/or the remaining lifetimes of one or more TAs received at stage6.

At stage 8 the cell change or handover to a second radio cell isperformed. The cell change may be performed when the UE 105 is in anidle state, e.g., as discussed at stage 8 a. The handover may beperformed when the UE 105 is in a connected state, as discussed atstages 8 a, 8 b, 8 c, and 8 d.

At stage 8 a, the UE 105 may obtain signal measurements for a secondradio cell from second SV2 102/202/302-2. The signal measurements forthe second radio cell, for example, may indicate support for the servingPLMN and an allowed TA for UE 105, and may include a SIB broadcast withthe remaining lifetime for the second radio cell, similar to the SIBbroadcast for the first radio cell discussed in stage 6. If the UE 105is in an idle state, the UE 105 may select the second radio cell to campon prior to the change of the first radio cell, e.g., based in part on aremaining lifetime for the second radio cell being greater than theremaining lifetime for the first radio cell, or based on a remaininglifetime for an allowed TA supported by the second radio cell beinggreater than the remaining lifetime for any allowed TA supported by thefirst radio cell.

At stage 8 b, if the UE 105 is in a connected state, the UE 105 mayprovide the signal measurements, for the second radio cell to the sNB106/202/307 via the first SV1 102/202/302-1.

At stage 8 c, the sNB 106/202/307 instigates handover of UE 105 to thesecond radio cell via signaling through the first SV1 102/202/302-1. Forexample, sNB 106/202/307 may instigate the handover based in part on thesignal measurements and the remaining lifetime for the second radio cellbeing greater than the remaining lifetime for the first radio cell or aremaining lifetime for an allowed TA for UE 106 supported by the secondradio cell being greater than the remaining lifetime for any allowed TAfor UE 105 supported by the first radio cell.

At stage 8 d, the handover to the second radio cell via the second SV2102/202/302-2 is performed.

At stage 9, the UE 105 may access the serving PLMN via the SV2102/202/302-2, sNB 106/202/307, and AMF 122, via the second radio cell.The access may be as described for stage 3 with the second radio celland SV2 102/202/302-2 replacing the first radio cell and SV1102/202/302-1.

FIG. 39 is a diagram illustrating an example of a hardwareimplementation of UE 3900, such as UE 105 shown in FIGS. 1, 2, and 3.The UE 3900 may perform the process flows 4700, 5100, 5600, and 5700 ofFIGS. 47, 51, 56 and 57. The UE 3900 may include, e.g., hardwarecomponents such as a satellite transceiver 3903 to wirelesslycommunicate directly with a SV 102, 202, 302, via signals 3930 that aresent and received using wireless antenna 3931, e.g., as shown in FIGS.1, 2, and 3. The UE 3900 may further include wireless transceiver 3902to wirelessly communicate directly with terrestrial base stations in anNG-RAN 112, via signals 3940 that are sent and received using wirelessantenna 3941, e.g., base stations such as gNB 114 or an ng-eNB. In someimplementations, satellite transceiver 3903 and wireless transceiver3902 may be combined—e.g. may be the same transceiver. The UE 3900 mayalso include additional transceivers, such a wireless local area network(WLAN) transceiver 3906, that may send and receive signals 3950 usingantenna 3951, as well as an SPS receiver 3908 for receiving andmeasuring signals 3960 using antenna 3961, from SPS SVs 190 (shown inFIGS. 1, 2, and 3). In some implementations, one or more of wirelessantennas 3931, 3941, 3951 and 3961 may be the same antenna. In someimplementations, the UE 3900 may receive data from a satellite, e.g.,via satellite transceiver 3903, and may respond to a terrestrial basestation, e.g., via wireless transceiver 3902, or via WLAN transceiver3906. Thus, UE 3900 may include one or more transmitters, one or morereceivers or both, and these may be integrated, discrete, or acombination of both. The UE 3900 may further include one or more sensors3910, such as cameras, accelerometers, gyroscopes, electronic compass,magnetometer, barometer, etc. The UE 3900 may further include a userinterface 3912 that may include e.g., a display, a keypad or other inputdevice, such as virtual keypad on the display, through which a user mayinterface with the UE 3900. The UE 3900 further includes one or moreprocessors 3904, memory 3916, and non-transitory computer readablemedium 3918, which may be coupled together with bus 3915. The one ormore processors 3904 and other components of the UE 3900 may similarlybe coupled together with bus 3914, a separate bus, or may be directlyconnected together or coupled using a combination of the foregoing.

The one or more processors 3904 may be implemented using a combinationof hardware, firmware, and software. For example, the one or moreprocessors 3904 may be configured to perform the functions discussedherein by implementing one or more instructions or program code 3920 ona non-transitory computer readable medium, such as medium 3918 and/ormemory 3916. In some embodiments, the one or more processors 3904 mayrepresent one or more circuits configurable to perform at least aportion of a data signal computing procedure or process related to theoperation of UE 3900.

The medium 3918 and/or memory 3916 may store instructions or programcode 3920 that contain executable code or software instructions thatwhen executed by the one or more processors 3904 cause the one or moreprocessors 3904 to operate as a special purpose computer programmed toperform the techniques disclosed herein (e.g. such as the process flows4700, 5100, 5600, and 5700 of FIGS. 47, 51, 56 and 57). As illustratedin UE 3900, the medium 3918 and/or memory 3916 may include one or morecomponents or modules that may be implemented by the one or moreprocessors 3904 to perform the methodologies described herein. While thecomponents or modules are illustrated as software in medium 3918 that isexecutable by the one or more processors 3904, it should be understoodthat the components or modules may be stored in memory 3916 or may bededicated hardware either in the one or more processors 3904 or off theprocessors.

A number of software modules and data tables may reside in the medium3918 and/or memory 3916 and be utilized by the one or more processors3904 in order to manage both communications and the functionalitydescribed herein. It should be appreciated that the organization of thecontents of the medium 3918 and/or memory 3916 as shown in UE 3900 ismerely exemplary, and as such the functionality of the modules and/ordata structures may be combined, separated, and/or be structured indifferent ways depending upon the implementation of the UE 3900.

The methodologies described herein may be implemented by various meansdepending upon the application. For example, these methodologies may beimplemented in hardware, firmware, software, or any combination thereof.For a hardware implementation, the one or more processors 3904 may beimplemented within one or more application specific integrated circuits(ASICs), digital signal processors (DSPs), digital signal processingdevices (DSPDs), programmable logic devices (PLDs), field programmablegate arrays (FPGAs), processors, controllers, micro-controllers,microprocessors, electronic devices, other electronic units designed toperform the functions described herein, or a combination thereof.

For an implementation of UE 3900 involving firmware and/or software, themethodologies may be implemented with modules (e.g., procedures,functions, and so on) that perform the separate functions describedherein. Any machine-readable medium tangibly embodying instructions maybe used in implementing the methodologies described herein. For example,software codes may be stored in a medium 3918 or memory 3916 andexecuted by one or more processors 3904, causing the one or moreprocessors 3904 to operate as a special purpose computer programmed toperform the techniques disclosed herein. Memory may be implementedwithin the one or processors 3904 or external to the one or moreprocessors 3904. As used herein the term “memory” refers to any type oflong term, short term, volatile, nonvolatile, or other memory and is notto be limited to any particular type of memory or number of memories, ortype of media upon which memory is stored.

If implemented in firmware and/or software, the functions performed byUE 3900 may be stored as one or more instructions or code on anon-transitory computer-readable storage medium such as medium 3918 ormemory 3916. Examples of storage media include computer-readable mediaencoded with a data structure and computer-readable media encoded with acomputer program. Computer-readable media includes physical computerstorage media. A storage medium may be any available medium that may beaccessed by a computer. By way of example, and not limitation, suchcomputer-readable media may comprise RAM, ROM, EEPROM, CD-ROM or otheroptical disk storage, magnetic disk storage, semiconductor storage, orother storage devices, or any other medium that may be used to storedesired program code in the form of instructions or data structures andthat may be accessed by a computer; disk and disc, as used herein,includes compact disc (CD), laser disc, optical disc, digital versatiledisc (DVD), floppy disk and Blu-ray disc where disks usually reproducedata magnetically, while discs reproduce data optically with lasers.Combinations of the above should also be included within the scope ofcomputer-readable media.

In addition to storage on computer-readable storage medium, instructionsand/or data for UE 3900 may be provided as signals on transmission mediaincluded in a communication apparatus. For example, a communicationapparatus comprising part or all of UE 3900 may include a transceiverhaving signals indicative of instructions and data. The instructions anddata are stored on non-transitory computer readable medium 3918 ormemory 3916, and are configured to cause the one or more processors 3904to operate as a special purpose computer programmed to perform thetechniques disclosed herein. That is, the communication apparatusincludes transmission media with signals indicative of information toperform disclosed functions. At a first time, the transmission mediaincluded in the communication apparatus may include a first portion ofthe information to perform the disclosed functions, while at a secondtime the transmission media included in the communication apparatus mayinclude a second portion of the information to perform the disclosedfunctions.

FIG. 40 is a diagram illustrating an example of a one or more componentsor modules of program code 3920 that may be stored in the medium 3918and/or memory 3916 of the UE 3900, that when implemented by the one ormore processors 3904, cause the one or more processors to perform themethodologies described herein. While the components or modules areillustrated as software in medium 3918 and/or memory 3916 that isexecutable by the one or more processors 3904, it should be understoodthat the components or modules may be firmware or dedicated hardwareeither in the one or more processors 3904 or off the processors.

As illustrated, the program code 3920 stored on medium 3918 and/ormemory 3916 may include a configuration data module 4002 that that whenimplemented by the one or more processors 3904 configures the one ormore processors 3904 to receive configuration data from a network nodevia a communication satellite via the satellite transceiver 3903. Theconfiguration data may include information for fixed cells and fixedtracking areas in wireless coverage of the communications satellite andassociated with the serving PLMN, wherein the fixed cells and the fixedtracking areas are defined as fixed geographic areas and wherein thefixed cells and the fixed tracking area are defined independently ofeach other. As discussed above, for example, the fixed cells and fixedTAs are defined as fixed geographic areas and are defined independentlyof each other. Each fixed cell is assigned a cell identifier and eachfixed TAs is assigned a tracking area code and a color code, whereadjacent fixed TAs are assigned different color codes. The configurationinformation for the fixed cells may include locations of grid points inan array of grid points and cell identifiers associated with the arrayof grid points, e.g., where each grid point defines a fixed cell and hasone associated cell identifier.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude medium 3918 and/or memory 3916 may include a position module4004 that when implemented by the one or more processors 3904 configuresthe one or more processors 3904 to obtain a position of the UE, e.g.,using signal measurements from one or more of communication satellites,e.g., received by satellite transceiver 3903, Global NavigationSatellite System (GNSS) satellites received by SPS transceiver 3908, orterrestrial base stations received by wireless transceiver 3902 or acombination thereof.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude a PLMN identifier module 4006 that when implemented by the oneor more processors 3904 configures the one or more processors 3904 togenerate a unique PLMN identifier for the fixed serving cell using thecell identifier for the fixed serving cell and the color code for thefixed serving tracking area in which the UE is located, wherein theservice operation is performed based on the unique PLMN identifier.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude a registration module 4008 that when implemented by the one ormore processors 3904 configures the one or more processors 3904 toperform a registration with a serving core network in a serving PLMNassociated with the serving virtual cell and/or serving TA in which theUE is located via the satellite transceiver 903.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude a handover module 4010 that when implemented by the one or moreprocessors 3904 configures the one or more processors 3904 to perform ahandover from one satellite to another or from one PLMN to another.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude an EM call module 4012 that when implemented by the one or moreprocessors 3904 configures the one or more processors 3904 to initiatean emergency call to a public safety answering point (PSAP) associatedwith the serving virtual cell and/or TA, e.g., using the unique PLMNidentifier.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude a WEA module 4014 that when implemented by the one or moreprocessors 3904 configures the one or more processors 3904 to supportWireless Emergency Alerting (WEA) associated with the serving virtualcell and/or TA.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude a country module 4016 that when implemented by the one or moreprocessors 3904 configures the one or more processors 3904 to obtain thecountry of the UE based on the location of the UE, e.g., by determiningthe country based on the location of the UE based on a determinedlocation of the UE and location related information for supported PLMNs,or by receiving an indication of the country from an sNB in response toa request to access a PLMN, which may include the location of the UE asdetermined by the UE.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude a detect radio cell module 4018 that when implemented by the oneor more processors 3904 configures the one or more processors 3904 todetect radio cells that are available to the UE that include one or moreradio beams transmitted from an SV.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude a supported PLMNs module 4020 that when implemented by the oneor more processors 3904 configures the one or more processors 3904 toreceive identities of supported PLMNs that are broadcast in one or morefirst radio cells, the identity of each supported PLMN indicates acountry for the PLMN, and location related information for the supportedPLMNs, such as the geographic definition for fixed cells of the eachsupported PLMN, geographic definition for fixed tracking areas of theeach supported PLMN or both.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude a select PLMN module 4022 that when implemented by the one ormore processors 3904 configures the one or more processors 3904 toselect a serving PLMN that is a PLMN for the country of the UE and isincluded in the supported PLMNs.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude a select radio cell module 4024 that when implemented by the oneor more processors 3904 configures the one or more processors 3904 toselect a radio cell from available radio cells that support the servingPLMN.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude a PLMN access module 4026 that when implemented by the one ormore processors 3904 configures the one or more processors 3904 toaccess the serving PLMN using the selected radio cell, e.g., byexchanging signaling with the serving PLMN via the SV and a serving sNB.For example, the one or more processors 3904 may be configured to send arequest to access a PLMN. The one or more processors 3904 may beconfigured to send to an sNB a location of the UE as part of a requestto access a PLMN. The one or more processors 3904 may be configured toreceive security information from a sNB and to cipher the location ofthe UE based on the security information, and send the ciphered locationof the UE to the sNB as part of the request to access the PLMN. The oneor more processors 3904 may be configured to send the request to accessthe PLMN in a RRC Setup Request or an RRC Setup Complete message and mayreceive the country of the UE from a sNB in an RRC Setup message or anRRC Reject message. The one or more processors 3904, for example, may beconfigured to map a current location to an allowed TA and/or fixed celland provide an indication of the allowed TA and/or fixed cell to theserving PLMN to enable a service for the UE by the serving PLMN.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude a registration module 4028 that when implemented by the one ormore processors 3904 configures the one or more processors 3904 toregister with the serving PLMN. For example, the one or more processors3904, may be configured to send an NAS Registration request message,e.g., in a RRC Setup Complete message, to a network node and receive aNAS Registration Accept message, that may include allowed TAs for theserving PLMN and identities and a geographic definition for a pluralityof fixed cells of the serving PLMN. The one or more processors 3904 maybe configured to re-register with the serving PLMN for a change of TA.For example, the one or more processors 3904 may be configured todetermine if supported TAs identified by newly detected radio cells,which support the PLMN are included in previously received allowed TAsfor the serving PLMN. Registration may be performed for a change of TAusing the newly detected radio cell, e.g., if the NAS RegistrationAccept messaged indicates, e.g., with a Registration flag that it isrequired. The UE may camp on the newly detected radio cell withoutregistration for the change of TA, e.g., if the UE is in an idle stateand registration is not required. The UE may access the serving PLMNusing the newly detected radio cell without registration for the changeof TA, e.g., if the UE is in a connected state and registration is notrequired. In another example, the one or more processors may beconfigured to determine whether a current location of the UE is insideany allowed TA. The UE may register for the change of TA when thecurrent location is not inside any allowed TA or when the currentlocation of the UE is inside an allowed TA and the allowed TA is notincluded in the plurality of supported TAs. The UE may not be requiredto register for the change of TA if the current location of the UE isinside any allowed TA and the allowed TA is included in a supported TAs,and the newly detected radio cell indicates support for the allowed TA.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude an access PLMN module 4030 that when implemented by the one ormore processors 3904 configures the one or more processors 3904 toaccess a serving PLMN via a radio cell for a SV before and after ahandover or cell change. The one or more processors 3904 may beconfigured to access the serving PLMN via the SV and the radio cell forthe SV if it is determined that the UE is located inside the allowed TAand it is determined that the radio cell supports the serving PLMN andthe allowed TA. The one or more processors 3904 may be configured toaccess the serving PLMN via the SV and the radio cell when it isdetermined that the serving PLMN and the allowed TA are supported by theradio cell and when the UE is either located inside the allowed TA ornot located inside the allowed TA, if an indication is received that theUE may access the serving PLMN via the SV and the radio cell for the SVwhen the UE is not located in the allowed TA.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude an lifetime module 4032 that when implemented by the one or moreprocessors 3904 configures the one or more processors 3904 to receive aremaining lifetime for a radio cell broadcast by a SV in a SIB, such asa SIB1 or SIB2, in the first radio cell. The remaining lifetime may bean amount of time until a change of the radio cell, which may include achange of an earth station used to exchange signaling for the radio cellbetween the first SV and a satellite NodeB (sNB) for the radio cell, achange in timing for the radio cell; a change in carrier frequency forthe radio cell; a change in bandwidth for the radio cell; a change incoverage area for the radio cell; a change to radio beams used by theradio cell; a change in a cell identity for the radio cell; a cessationof support by the radio cell for one or more tracking areas for one ormore PLMNs supported by the radio cell; or a termination of support forthe radio cell by the sNB for the radio cell. The one or more processors3904 may be configured to receive a remaining lifetime for the allowedTA in the radio cell, e.g., where the remaining lifetime is broadcast bya SV in a SIB for the radio cell, and the remaining lifetime is anamount of time until the radio cell ceases support for the allowed TA.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude a cell change module 4034 that when implemented by the one ormore processors 3904 configures the one or more processors 3904 toperform a cell change to a different radio cell before a change of aradio cell, based on the remaining lifetime of the radio cell, and thenew radio cell indicating support for the serving PLMN and the allowedTA. The one or more processors 3904 may be configured to select a newradio cell prior to the cell change, when the UE is in an idle state,based in part on a remaining lifetime for the new radio cell beinggreater than the remaining lifetime for a current radio cell. The one ormore processors 3904 may be configured to perform a cell change to a newradio cell before a radio cell ceases support for an allowed TA, e.g.,based on the remaining lifetime of the allowed TA in the radio cell,wherein the new radio cell is different to the radio cell, and the newradio cell indicates support for the serving PLMN and the allowed TA.The one or more processors 3904 may be configured to select the newradio cell prior to the cell change based in part on a remaininglifetime for the allowed TA in the new radio cell which is greater thanthe remaining lifetime for the allowed TA in the first radio cell.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude a handover module 4036 that when implemented by the one or moreprocessors 3904 configures the one or more processors 3904 to perform ahandover to a different radio cell before a change of a radio cell,based on the remaining lifetime of the radio cell and the new radio cellindicating support for the serving PLMN and the allowed TA. The one ormore processors 3904 may be configured, when in a connected stated, toobtain signal measurements for a new radio cell prior to the handover,and send the signal measurements to a satellite NodeB (sNB) for thecurrent radio cell, wherein the sNB instigates the handover based inpart on the signal measurements and a remaining lifetime for the newradio cell being greater than the remaining lifetime for the currentradio cell. The one or more processors 3904 may be configured to performa handover to a new radio cell before a radio cell ceases support for anallowed TA, e.g., based on the remaining lifetime of the allowed TA inthe radio cell, wherein the new radio cell is different to the radiocell, and the new radio cell indicates support for the serving PLMN andthe allowed TA. The one or more processors 3904 may be configured, whenin a connected stated, to obtain signal measurements for the new radiocell prior to the handover, and send the signal measurements to asatellite NodeB (sNB) for the first radio cell, wherein the sNBinstigates the handover based in part on the signal measurements and aremaining lifetime for the allowed TA in the new radio cell which isgreater than the remaining lifetime for the allowed TA in the firstradio cell.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude an allowed TAs module 4038 that when implemented by the one ormore processors 3904 configures the one or more processors 3904 toreceive an indication of an allowed tracking area (TA) for a servingPLMN from the serving PLMN, the UE being allowed to access the servingPLMN based on the allowed TA.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude a PLMN support module 4040 that when implemented by the one ormore processors 3904 configures the one or more processors 3904 toreceive an indication in an available radio cell for a SV for supportfor a serving PLMN and allowed TA for by the radio cell.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude a location in TA module 4042 that when implemented by the one ormore processors 3904 configures the one or more processors 3904 todetermine whether the UE is located inside an allowed TA.

The program code 3920 stored on medium 3918 and/or memory 3916 mayinclude an access when not in TA module 4044 that when implemented bythe one or more processors 3904 configures the one or more processors3904 to access the serving PLMN via the SV and the radio cell for the SVwhen the UE is not located in the allowed TA.

FIG. 41 is a diagram illustrating an example of a hardwareimplementation of a satellite node B (sNB) 4100. sNB 4100 may correspondto any of: (i) sNB 106, sNB-DU 104-3 or 104-4 or sNB-CU 107 illustratedin FIG. 1; (ii) sNB 202 in the SV 202 illustrated in FIG. 2; or (iii)sNB-DU 302 in the SV 302 or sNB-CU 307 illustrated in FIG. 3. The sNB4100 may perform the process flows 4800, 5000, 5200, 5400, and 5500 ofFIGS. 48, 50, 52, 54, and 55. The sNB 4100 may include, e.g., hardwarecomponents such as an external interface 4106, which may comprise one ormore wired and/or wireless interfaces capable of connecting to anddirectly communicating with one or more entities in a core network in aPLMN, such as AMF 122 or UPF 130 in 5GCN 110 shown in FIGS. 1-3, andearth stations 104, as well as other sNBs, UEs 105 (e.g. when sNB 4100is part of an SV 202 or SV 302) and to other elements in a wirelessnetwork directly or through one or more intermediary networks and/or oneor more network entities, as shown in FIGS. 1, 2, and 3. The externalinterface 4106 may include one or more antennas (not shown in FIG. 41)to support a wireless interface and/or a wireless backhaul to elementsin the wireless network. The sNB 4100 further includes one or moreprocessors 4104, memory 4116, and non-transitory computer readablemedium 4118, which may be coupled together with bus 4107. The sNB 4100is illustrated as including an sNB-DU 4112 and/or sNB-CU 4114 (e.g. inthe case that sNB 4100 corresponds to sNB 106-3 in FIG. 1, an sNB 202 inFIG. 2, or an sNB-DU 302 or sNB-CU 307 in FIG. 3), which may be hardwarecomponents or implemented by specifically configured one or moreprocessors 4104. One or both of sNB-DU 4112 and sNB-CU 4114 may not bepresent, e.g. when sNB 4100 corresponds to just an sNB-DU (e.g. sNB-DU302) or to just an sNB-CU (e.g. sNB-CU 307) or when sNB 4100 does notuse a split architecture.

The one or more processors 4104 may be implemented using a combinationof hardware, firmware, and software. For example, the one or moreprocessors 4104 may be configured to perform the functions discussedherein by implementing one or more instructions or program code 4120 ona non-transitory computer readable medium, such as medium 4118 and/ormemory 4116. In some embodiments, the one or more processors 4104 mayrepresent one or more circuits configurable to perform at least aportion of a data signal computing procedure or process related to theoperation of sNB 4100.

The medium 4118 and/or memory 4116 may store instructions or programcode 4120 that contain executable code or software instructions thatwhen executed by the one or more processors 4104 cause the one or moreprocessors 4104 to operate as a special purpose computer programmed toperform the techniques disclosed herein (e.g. such as the process flows4800, 5000, 5200, 5400, and 5500 of FIGS. 48, 50, 52, 54, and 55). Asillustrated in sNB 4100, the medium 4118 and/or memory 4116 may includeone or more components or modules that may be implemented by the one ormore processors 4104 to perform the methodologies described herein.While the components or modules are illustrated as software in medium4118 that is executable by the one or more processors 4104, it should beunderstood that the components or modules may be stored in memory 4116or may be dedicated hardware either in the one or more processors 4104or off the processors.

A number of software modules and data tables may reside in the medium4118 and/or memory 4116 and be utilized by the one or more processors4104 in order to manage both communications and the functionalitydescribed herein. It should be appreciated that the organization of thecontents of the medium 4118 and/or memory 4116 as shown in sNB 4100 ismerely exemplary, and as such the functionality of the modules and/ordata structures may be combined, separated, and/or be structured indifferent ways depending upon the implementation of the sNB 4100.

The methodologies described herein may be implemented by various meansdepending upon the application. For example, these methodologies may beimplemented in hardware, firmware, software, or any combination thereof.For a hardware implementation, the one or more processors 4104 may beimplemented within one or more application specific integrated circuits(ASICs), digital signal processors (DSPs), digital signal processingdevices (DSPDs), programmable logic devices (PLDs), field programmablegate arrays (FPGAs), processors, controllers, micro-controllers,microprocessors, electronic devices, other electronic units designed toperform the functions described herein, or a combination thereof.

For an implementation of sNB 4100 involving firmware and/or software,the methodologies may be implemented with modules (e.g., procedures,functions, and so on) that perform the separate functions describedherein. Any machine-readable medium tangibly embodying instructions maybe used in implementing the methodologies described herein. For example,software codes may be stored in a medium 4118 or memory 4116 andexecuted by one or more processors 4104, causing the one or moreprocessors 4104 to operate as a special purpose computer programmed toperform the techniques disclosed herein. Memory may be implementedwithin the one or processors 4104 or external to the one or moreprocessors 4104. As used herein the term “memory” refers to any type oflong term, short term, volatile, nonvolatile, or other memory and is notto be limited to any particular type of memory or number of memories, ortype of media upon which memory is stored.

If implemented in firmware and/or software, the functions performed bysNB 4100 may be stored as one or more instructions or code on anon-transitory computer-readable storage medium such as medium 4118 ormemory 4116. Examples of storage media include computer-readable mediaencoded with a data structure and computer-readable media encoded with acomputer program. Computer-readable media includes physical computerstorage media. A storage medium may be any available medium that may beaccessed by a computer. By way of example, and not limitation, suchcomputer-readable media may comprise RAM, ROM, EEPROM, CD-ROM or otheroptical disk storage, magnetic disk storage, semiconductor storage, orother storage devices, or any other medium that may be used to storedesired program code in the form of instructions or data structures andthat may be accessed by a computer; disk and disc, as used herein,includes compact disc (CD), laser disc, optical disc, digital versatiledisc (DVD), floppy disk and Blu-ray disc where disks usually reproducedata magnetically, while discs reproduce data optically with lasers.Combinations of the above should also be included within the scope ofcomputer-readable media.

In addition to storage on computer-readable storage medium, instructionsand/or data for sNB 4100 may be provided as signals on transmissionmedia included in a communication apparatus. For example, acommunication apparatus comprising part or all of sNB 4100 may include atransceiver having signals indicative of instructions and data. Theinstructions and data are stored on non-transitory computer readablemedia, e.g., medium 4118 or memory 4116, and are configured to cause theone or more processors 4104 to operate as a special purpose computerprogrammed to perform the techniques disclosed herein. That is, thecommunication apparatus includes transmission media with signalsindicative of information to perform disclosed functions. At a firsttime, the transmission media included in the communication apparatus mayinclude a first portion of the information to perform the disclosedfunctions, while at a second time the transmission media included in thecommunication apparatus may include a second portion of the informationto perform the disclosed functions.

FIG. 42 is a diagram illustrating an example of a one or more componentsor modules of program code 4120 that may be stored in the medium 4118and/or memory 4116 of the sNB 4100, that when implemented by the one ormore processors 4104, cause the one or more processors to perform themethodologies described herein. While the components or modules areillustrated as software in medium 4118 and/or memory 4116 that isexecutable by the one or more processors 4104, it should be understoodthat the components or modules may be firmware or dedicated hardwareeither in the one or more processors 4104 or off the processors.

As illustrated, the program code 4120 stored on medium 4118 and/ormemory 4116 may include a configuration data module 4202 that that whenimplemented by the one or more processors 4104 configures the one ormore processors 4104 to transmit configuration data to the UE via theexternal interface 4106, and/or to receive configuration data from anetwork node via the external interface 4106. The configuration datacomprising information for fixed cells and fixed tracking areas inwireless coverage of the communications satellite and associated withthe serving PLMN, wherein the fixed cells and the fixed tracking areasare defined as fixed geographic areas and wherein the fixed cells andthe fixed tracking area are defined independently of each other.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude a position module 4204 that when implemented by the one or moreprocessors 4104 configures the one or more processors 4104 to receive aposition for the UE, via the external interface 4106, e.g., in a requestfrom the UE to access the PLMN, or to determine the position of the UEbased on a coverage area of a radio cell or radio beam of the sNB usedby the UE.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude a position transmit module 4206 that when implemented by the oneor more processors 4104 configures the one or more processors 4104 totransmit the position of the UE to a network entity, via the externalinterface 4106.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude a service operation module 4208 that when implemented by the oneor more processors 4104 configures the one or more processors 4104 toenable a service operation, e.g., WEA, LI or EN, for the UE by a servingcore network for the serving PLMN based on at least one of the fixedserving cell and the fixed serving tracking area, e.g., using theexternal interface 4106.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude a fixed cell and TA module 4210 that when implemented by the oneor more processors 4104 configures the one or more processors 4104 todetermine a fixed serving cell and a fixed serving tracking area inwhich the UE is located based on the position of the UE and theconfiguration information for the fixed cells and the fixed trackingareas.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude a PLMN identifier module 4212 that when implemented by the oneor more processors 4104 configures the one or more processors 4104 togenerate a unique PLMN identifier for the fixed serving cell using thecell identifier for the fixed serving cell and the color code for thefixed serving tracking area in which the UE is located, wherein theservice operation is performed based on the unique PLMN identifier.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude a transport signaling module 4214 that when implemented by theone or more processors 4104 configures the one or more processors 4104to transport signaling using the external interface 4106, between UEsand core network, e.g., before and after transfer, where the signalingis transported via an SV and earth stations, and is transported betweenthe SV and the UEs using radio cells.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude a handover module 4216 that when implemented by the one or moreprocessors 4104 configures the one or more processors 4104 to handoverthe signaling from a first earth station to a second earth station,e.g., by ceasing the transport of signaling via the first earth stationand to enable transport of the signaling via the second earth station.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude a timing module 4218 that when implemented by the one or moreprocessors 4104 configures the one or more processors 4104 to determinea timing for each radio cell and to provide the timing of a servingradio cell to each UE before the transfer to a new earth station. Theone or more processors 4104 may be configured to determine the timing,for example, based on (i) a known orbital position of the SV, and (ii)known or measured propagation and transmission delays for: signalinglinks between the sNB and the first earth station, signaling linksbetween the first earth station and the SV; signaling links between thesNB and the second earth station; signaling links between the secondearth station and the SV; and signaling links between the SV and theUEs.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude a timing advance module 4220 that when implemented by the one ormore processors 4104 configures the one or more processors 4104 todetermine a timing advance for each UE, the timing advance applicableafter the transfer to a new earth station, and provide the timingadvance to each UE before the transfer.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude a data link transfer module 4222 that when implemented by theone or more processors 4104 configures the one or more processors 4104to transfer a plurality of data links from a first earth station to asecond earth station. The data links in the plurality of data links maycomprise a Level 2 connection between the sNB and the core network orbetween the sNB-DU and the sNB-CU, and the signaling for each data linkin the plurality of data links may be transported through the earthstations at a Level 1 prior to and after the transfer.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude a release module 4224 that when implemented by the one or moreprocessors 4104 configures the one or more processors 4104 to release,prior to a transfer between earth stations, data links between the sNBand the core network or between the sNB-DU and the sNB-CU. The pluralityof data links transporting the signaling, and each data link in thefirst plurality of data links may comprise a Level 2 connection betweenthe sNB and the first earth station and a concatenated Level 2connection between the first earth station and the core network or aLevel 2 connection between the sNB-DU or the sNB-CU and the first earthstation and a concatenated Level 2 connection between the first earthstation and the other of the sNB-DU and the sNB-CU. The one or moreprocessors may be further configured to release non-UE associated linksand connections and/or UE associated connections and tunnels between thesNB-DU and the sNB-CU, and core network, immediately before transfer,wherein signaling for the non-UE associated links and connections istransported between the sNB-DU and the sNB-CU via the first earthstation at a Level 1 or a Level 2, and signaling for the UE associatedconnections and tunnels is transported between the sNB-DU and the sNB-CUusing the non-UE associated links and connections.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude a transfer module 4226 that when implemented by the one or moreprocessors 4104 configures the one or more processors 4104 to transferfrom a first earth station to a second earth station, a Level 1transport of signaling between the sNB and the core network or betweenthe sNB-DU or the sNB-CU and the other of the sNB-DU and the sNB-CU.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude an establish module 4228 that when implemented by the one ormore processors 4104 configures the one or more processors 4104 toestablish after the transfer data links between the sNB and the corenetwork or between the sNB-DU or the sNB-CU and the other of the sNB-DUand the sNB-CU. The data links transporting the signaling, and maycomprise a Level 2 connection between the sNB and the new earth stationand a concatenated Level 2 connection between the new earth station andthe core network or a Level 2 connection between the sNB-DU or thesNB-CU and the new earth station and a concatenated Level 2 connectionbetween the second earth station and the other of the sNB-DU and thesNB-CU. The one or more processors may be further configured toestablish non-UE associated links and connections or UE associatedconnections and tunnels between the sNB-DU and the sNB-CU and the corenetwork immediately after the transfer, wherein signaling for the non-UEassociated links and connections is transported between the sNB-DU andthe second sNB-CU via the new earth station at a Level 1 or a Level 2,and signaling for the UE associated connections and tunnels istransported between the sNB-DU and the sNB-CU via the new earth stationusing the non-UE associated links and connections.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude an SIB (supported PLMNS) module 4230 that when implemented bythe one or more processors 4104 configures the one or more processors4104 to control an SV to broadcast system information blocks (SIBs) ineach of one or more radio cells of the sNB, the SIBs includingidentities of supported PLMNs for the sNB and the identity of eachsupported PLMN indicates a country for the each supported PLMN. Theidentity of the supported PLMNS may include a MCC and an MNC. The one ormore processors 4104 may be further configured to send securityinformation to the UE, with which the UE may cipher its location.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude a PLMN access request module 4232 that when implemented by theone or more processors 4104 configures the one or more processors 4104to receive a request to access a PLMN from an UE via one of the radiocells of the sNB. The PLMN access request may be an RRC Setup Request oran RRC Setup Complete message.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude a country module 4234 that when implemented by the one or moreprocessors 4104 configures the one or more processors 4104 to obtain alocation of the UE and determine the country of the UE based on thelocation. For example, the one or more processors 4104 may be configuredto receive the location of the UE from the UE in the request to accessthe PLMN. The one or more processors 4104 may be configured to decipherthe location received from the UE when the UE ciphers the location usingsecurity information provided by the sNB. The one or more processors4104 may be configured to determine the location based on a coveragearea of the one of the one or more radio cells of the sNB or a coveragearea for a radio beam of the one of the one or more radio cells of thesNB, wherein the radio beam is used by the UE to send the request toaccess the PLMN to the sNB.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude a PLMN access response module 4236 that when implemented by theone or more processors 4104 configures the one or more processors 4104to send to the UE the country of the UE. The one or more processors 4104may be configured to provide an PLMN access response, such as an RRCSetup message or RRC Setup Reject message, which may include the countryof the UE. The one or more processors 4104, for example, may beconfigured to determine whether the country of the UE is supported bythe sNB and send an RRC Setup message if the country is supported or RRCSetup Reject messaged if the country is not supported.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude a registration module 4238 that when implemented by the one ormore processors 4104 configures the one or more processors 4104 toassist in registration of the UE with a serving PLMN. For example, theone or more processors 4104 may be configured to receive an NASRegistration Request message, e.g., in an RRC Setup Complete messagedfrom the UE, which may include an indication of a selected PLMN, and tosend an NGAP Initial UE message to an AMF of the selected PLMN thatincludes an indication of the fixed serving cell and fixed TA for theUE, which may be the location of the UE or identities of the fixedserving cell and fixed TA. The one or more processors 4104 may beconfigured to map the location of the UE to an identity of the fixedserving cell and an identity of the fixed TA.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude a lifetime module 4240 that when implemented by the one or moreprocessors 4104 configures the one or more processors 4104 to determinea remaining lifetime for a radio cell controlled by the sNB, wherein theremaining lifetime is an amount of time until a change of the radiocell. The remaining lifetime may be an amount of time until a change ofthe radio cell, which may include a change of an earth station used toexchange signaling for the radio cell between the first SV and asatellite NodeB (sNB) for the radio cell, a change in timing for theradio cell; a change in carrier frequency for the radio cell; a changein bandwidth for the radio cell; a change in coverage area for the radiocell; a change to radio beams used by the radio cell; a change in a cellidentity for the radio cell; a cessation of support by the radio cellfor one or more tracking areas for one or more PLMNs supported by theradio cell; or a termination of support for the radio cell by the sNBfor the radio cell.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude a determine supported TAs module 4242 that when implemented bythe one or more processors 4104 configures the one or more processors4104 to determine a plurality of tracking areas (TAs) currentlysupported by a radio cell controlled by the sNB, wherein the pluralityof TAs belong to a plurality of PLMNs supported by the radio cell. Theone or more processors 4104 may be configured to determine TAs withgeographic areas overlapping with a coverage area of the radio cell, andwhere the overlap between the geographic area of each TA of the TAs andthe coverage area of the radio cell satisfies one or more criteria foreach TA of the TAs. The criteria for each TA for example may comprise:inclusion of the geographic area of the each TA within the coverage areaof the radio cell; inclusion of the coverage area of the radio cellwithin the geographic area of the each TA; an overlap of the coveragearea of the radio cell with the geographic area of the each TA whichexceeds a threshold for the each TA; or some combination of these.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude an SIB module 4244 that when implemented by the one or moreprocessors 4104 configures the one or more processors 4104 to generatinga system information block (SIB), e.g., a type 1 SIB or a type 2 SIB,indicating the remaining lifetime of the radio cell and/or indicatingeach of a plurality of TAs supported by a radio cell controlled by thesNB and the remaining lifetime for each TA in the plurality of TAs.

The program code 4120 stored on medium 4118 and/or memory 4116 mayinclude a provide lifetime/TA module 4246 that when implemented by theone or more processors 4104 configures the one or more processors 4104to broadcast the remaining lifetime of the radio cell and/or the TAssupported by radio cell controlled by the sNB and the remaining lifetimefor each TA, via using an SV for the radio cell. For example, the one ormore processors 4104 may be configured to broadcast the SIB generated bythe SIB module 4244.

FIG. 43 is a diagram illustrating an example of a hardwareimplementation of an SV 4300, e.g., SV 102, 202, or 302, shown in FIGS.1, 2, and 3, that is configured to be in wireless communication with oneor more UEs 105 and earth stations 104. In some cases (e.g. when SV 4300corresponds to SV 202 in FIG. 2), SV 4300 may be in communication withone or more other SVs 4300. The SV 4300 includes, e.g., hardwarecomponents such as a wireless transceiver 4302 capable of directlycommunicating with UEs 105, as well as earth stations 104. In someimplementations, the SV 4300 may include an sNB 4306, e.g., if the SV4300 is a hardware implementation of SV 202 shown in FIG. 2. In anotherimplementation, the SV 4300 may include an sNB-DU 4308, e.g., if the SV4300 is a hardware implementation of SV 302 shown in FIG. 3. The sNB4306 or sNB 4308 may be hardware implementation or a softwareimplementation and may include structure and perform functions asdescribed in FIGS. 41 and 42. The satellite 4300 includes one or moreprocessors 4304, memory 4316, and non-transitory computer readablemedium 4118, which may be coupled together with bus 4307, along with sNB4306 or sNB-DU 4308 if implemented in hardware.

The one or more processors 4304 may be implemented using a combinationof hardware, firmware, and software. For example, the one or moreprocessors 4304 may be configured to perform the functions discussedherein by implementing one or more instructions or program code 4320 ona non-transitory computer readable medium, such as medium 4318 and/ormemory 4316. In some embodiments, the one or more processors 4304 mayrepresent one or more circuits configurable to perform at least aportion of a data signal computing procedure or process related to theoperation of SV 4300.

The medium 4318 and/or memory 4316 may store instructions or programcode 4320 that contain executable code or software instructions thatwhen executed by the one or more processors 4304 cause the one or moreprocessors 4304 to operate as a special purpose computer programmed toperform the techniques disclosed herein (e.g. such as the process flow4800 of FIG. 48). As illustrated in SV 4300, the medium 4318 and/ormemory 4316 may include one or more components or modules that may beimplemented by the one or more processors 4304 to perform themethodologies described herein. While the components or modules areillustrated as software in medium 4318 that is executable by the one ormore processors 4304, it should be understood that the components ormodules may be stored in memory 4316 or may be dedicated hardware eitherin the one or more processors 4304 or off the processors.

A number of software modules and data tables may reside in the medium4318 and/or memory 4316 and be utilized by the one or more processors4304 in order to manage both communications and the functionalitydescribed herein. It should be appreciated that the organization of thecontents of the medium 4318 and/or memory 4316 as shown in SV 4300 ismerely exemplary, and as such the functionality of the modules and/ordata structures may be combined, separated, and/or be structured indifferent ways depending upon the implementation of the SV 4300.

The methodologies described herein may be implemented by various meansdepending upon the application. For example, these methodologies may beimplemented in hardware, firmware, software, or any combination thereof.For a hardware implementation, the one or more processors 4304 may beimplemented within one or more application specific integrated circuits(ASICs), digital signal processors (DSPs), digital signal processingdevices (DSPDs), programmable logic devices (PLDs), field programmablegate arrays (FPGAs), processors, controllers, micro-controllers,microprocessors, electronic devices, other electronic units designed toperform the functions described herein, or a combination thereof.

For an implementation of SV 4300 involving firmware and/or software, themethodologies may be implemented with modules (e.g., procedures,functions, and so on) that perform the separate functions describedherein. Any machine-readable medium tangibly embodying instructions maybe used in implementing the methodologies described herein. For example,software codes may be stored in a medium 4318 or memory 4316 andexecuted by one or more processors 4304, causing the one or moreprocessors 4304 to operate as a special purpose computer programmed toperform the techniques disclosed herein. Memory may be implementedwithin the one or processors 4304 or external to the one or moreprocessors 4304. As used herein the term “memory” refers to any type oflong term, short term, volatile, nonvolatile, or other memory and is notto be limited to any particular type of memory or number of memories, ortype of media upon which memory is stored.

If implemented in firmware and/or software, the functions performed bySV 4300 may be stored as one or more instructions or code on anon-transitory computer-readable storage medium such as medium 4318 ormemory 4316. Examples of storage media include computer-readable mediaencoded with a data structure and computer-readable media encoded with acomputer program. Computer-readable media includes physical computerstorage media. A storage medium may be any available medium that may beaccessed by a computer. By way of example, and not limitation, suchcomputer-readable media may comprise RAM, ROM, EEPROM, CD-ROM or otheroptical disk storage, magnetic disk storage, semiconductor storage, orother storage devices, or any other medium that may be used to storedesired program code in the form of instructions or data structures andthat may be accessed by a computer; disk and disc, as used herein,includes compact disc (CD), laser disc, optical disc, digital versatiledisc (DVD), floppy disk and Blu-ray disc where disks usually reproducedata magnetically, while discs reproduce data optically with lasers.Combinations of the above should also be included within the scope ofcomputer-readable media.

In addition to storage on computer-readable storage medium, instructionsand/or data for SV 4300 may be provided as signals on transmission mediaincluded in a communication apparatus. For example, a communicationapparatus comprising part or all of SV 4300 may include a transceiverhaving signals indicative of instructions and data. The instructions anddata are stored on non-transitory computer readable media, e.g., medium4318 or memory 4316, and are configured to cause the one or moreprocessors 4304 to operate as a special purpose computer programmed toperform the techniques disclosed herein. That is, the communicationapparatus includes transmission media with signals indicative ofinformation to perform disclosed functions. At a first time, thetransmission media included in the communication apparatus may include afirst portion of the information to perform the disclosed functions,while at a second time the transmission media included in thecommunication apparatus may include a second portion of the informationto perform the disclosed functions.

FIG. 44 is a diagram illustrating an example of a one or more componentsor modules of program code 4320 that may be stored in the medium 4318and/or memory 4316 of the SV 4300, that when implemented by the one ormore processors 4304, cause the one or more processors to perform themethodologies described herein. While the components or modules areillustrated as software in medium 4318 and/or memory 4316 that isexecutable by the one or more processors 4304, it should be understoodthat the components or modules may be firmware or dedicated hardwareeither in the one or more processors 4304 or off the processors.

As illustrated, the program code 4320 stored on medium 4318 and/ormemory 4316 may include a configuration data module 4402 that that whenimplemented by the one or more processors 4304 configures the one ormore processors 4304 to transmit configuration data to the UE via theexternal interface 4306, and/or to receive configuration data from anetwork node via the external interface 4306. The configuration datacomprising information for fixed cells and fixed tracking areas inwireless coverage of the communications satellite and associated withthe serving PLMN, wherein the fixed cells and the fixed tracking areasare defined as fixed geographic areas and wherein the fixed cells andthe fixed tracking area are defined independently of each other.

The program code 4320 stored on medium 4318 and/or memory 4316 mayinclude a position module 4404 that when implemented by the one or moreprocessors 4304 configures the one or more processors 4304 to receive aposition for the UE, via the external interface 4306.

The program code 4320 stored on medium 4318 and/or memory 4316 mayinclude a position transmit module 4406 that when implemented by the oneor more processors 4304 configures the one or more processors 4304 totransmit the position of the UE to a network entity, via the externalinterface 4306.

The program code 4320 stored on medium 4318 and/or memory 4316 mayinclude a service operation module 4408 that when implemented by the oneor more processors 4304 configures the one or more processors 4304 toenable a service operation, e.g., WEA, LI or EN, for the UE by a servingcore network for the serving PLMN based on at least one of the fixedserving cell and the fixed serving tracking area, e.g., using theexternal interface 4306.

The program code 4320 stored on medium 4318 and/or memory 4316 mayinclude a fixed cell and TA module 4410 that when implemented by the oneor more processors 4304 configures the one or more processors 4304 todetermine a fixed serving cell and a fixed serving tracking area inwhich the UE is located based on the position of the UE and theconfiguration information for the fixed cells and the fixed trackingareas.

The program code 4320 stored on medium 4318 and/or memory 4316 mayinclude a PLMN identifier module 4412 that when implemented by the oneor more processors 4304 configures the one or more processors 4304 togenerate a unique PLMN identifier for the fixed serving cell using thecell identifier for the fixed serving cell and the color code for thefixed serving tracking area in which the UE is located, wherein theservice operation is performed based on the unique PLMN identifier.

FIG. 45 is a diagram illustrating an example of a hardwareimplementation of a core network entity 4500 in a serving PLMN, e.g.,such as AMF 122 or LMF 124, shown in FIGS. 1, 2, and 3, which sometimesmay be referred to herein as AMF 4500 or LMF 4500. The core networkentity 4500 includes, e.g., hardware components such as an externalinterface 4502 configured to be in direct communication with an sNB 106,sNB 307, earth station 104, LMF 124 and/or other core network entities,when the core network entity 4500 is an AMF, or configured tocommunicate with AMF 122 and other core network entities, when the corenetwork entity 4500 is an LMF. The core network entity 4500 includes oneor more processors 4504, memory 4516, and non-transitory computerreadable medium 4118, which may be coupled together with bus 4507.

The one or more processors 4504 may be implemented using a combinationof hardware, firmware, and software. For example, the one or moreprocessors 4504 may be configured to perform the functions discussedherein by implementing one or more instructions or program code 4520 ona non-transitory computer readable medium, such as medium 4518 and/ormemory 4516. In some embodiments, the one or more processors 4504 mayrepresent one or more circuits configurable to perform at least aportion of a data signal computing procedure or process related to theoperation of core network entity 4500.

The medium 4518 and/or memory 4516 may store instructions or programcode 4520 that contain executable code or software instructions thatwhen executed by the one or more processors 4504 cause the one or moreprocessors 4504 to operate as a special purpose computer programmed toperform the techniques disclosed herein (e.g. such as the process flows4800, 4900, and 5300 of FIGS. 48, 49, and 53). As illustrated in corenetwork entity 4500, the medium 4518 and/or memory 4516 may include oneor more components or modules that may be implemented by the one or moreprocessors 4504 to perform the methodologies described herein. While thecomponents or modules are illustrated as software in medium 4518 that isexecutable by the one or more processors 4504, it should be understoodthat the components or modules may be stored in memory 4516 or may bededicated hardware either in the one or more processors 4504 or off theprocessors.

A number of software modules and data tables may reside in the medium4518 and/or memory 4516 and be utilized by the one or more processors4504 in order to manage both communications and the functionalitydescribed herein. It should be appreciated that the organization of thecontents of the medium 4518 and/or memory 4516 as shown in core networkentity 4500 is merely exemplary, and as such the functionality of themodules and/or data structures may be combined, separated, and/or bestructured in different ways depending upon the implementation of thecore network entity 4500.

The methodologies described herein may be implemented by various meansdepending upon the application. For example, these methodologies may beimplemented in hardware, firmware, software, or any combination thereof.For a hardware implementation, the one or more processors 4504 may beimplemented within one or more application specific integrated circuits(ASICs), digital signal processors (DSPs), digital signal processingdevices (DSPDs), programmable logic devices (PLDs), field programmablegate arrays (FPGAs), processors, controllers, micro-controllers,microprocessors, electronic devices, other electronic units designed toperform the functions described herein, or a combination thereof.

For an implementation of core network entity 4500 involving firmwareand/or software, the methodologies may be implemented with modules(e.g., procedures, functions, and so on) that perform the separatefunctions described herein. Any machine-readable medium tangiblyembodying instructions may be used in implementing the methodologiesdescribed herein. For example, software codes may be stored in a medium4518 or memory 4516 and executed by one or more processors 4504, causingthe one or more processors 4504 to operate as a special purpose computerprogrammed to perform the techniques disclosed herein. Memory may beimplemented within the one or processors 4504 or external to the one ormore processors 4504. As used herein the term “memory” refers to anytype of long term, short term, volatile, nonvolatile, or other memoryand is not to be limited to any particular type of memory or number ofmemories, or type of media upon which memory is stored.

If implemented in firmware and/or software, the functions performed bycore network entity 4500 may be stored as one or more instructions orcode on a non-transitory computer-readable storage medium such as medium4518 or memory 4516. Examples of storage media include computer-readablemedia encoded with a data structure and computer-readable media encodedwith a computer program. Computer-readable media includes physicalcomputer storage media. A storage medium may be any available mediumthat may be accessed by a computer. By way of example, and notlimitation, such computer-readable media may comprise RAM, ROM, EEPROM,CD-ROM or other optical disk storage, magnetic disk storage,semiconductor storage, or other storage devices, or any other mediumthat may be used to store desired program code in the form ofinstructions or data structures and that may be accessed by a computer;disk and disc, as used herein, includes compact disc (CD), laser disc,optical disc, digital versatile disc (DVD), floppy disk and Blu-ray discwhere disks usually reproduce data magnetically, while discs reproducedata optically with lasers. Combinations of the above should also beincluded within the scope of computer-readable media.

In addition to storage on computer-readable storage medium, instructionsand/or data for core network entity 4500 may be provided as signals ontransmission media included in a communication apparatus. For example, acommunication apparatus comprising part or all of core network entity4500 may include a transceiver having signals indicative of instructionsand data. The instructions and data are stored on non-transitorycomputer readable media, e.g., medium 4518 or memory 4516, and areconfigured to cause the one or more processors 4504 to operate as aspecial purpose computer programmed to perform the techniques disclosedherein. That is, the communication apparatus includes transmission mediawith signals indicative of information to perform disclosed functions.At a first time, the transmission media included in the communicationapparatus may include a first portion of the information to perform thedisclosed functions, while at a second time the transmission mediaincluded in the communication apparatus may include a second portion ofthe information to perform the disclosed functions.

FIG. 46 is a diagram illustrating an example of a one or more componentsor modules of program code 4520 that may be stored in the medium 4518and/or memory 4516 of the core network entity 4500, that whenimplemented by the one or more processors 4504, cause the one or moreprocessors to perform the methodologies described herein. While thecomponents or modules are illustrated as software in medium 4518 and/ormemory 4516 that is executable by the one or more processors 4504, itshould be understood that the components or modules may be firmware ordedicated hardware either in the one or more processors 4504 or off theprocessors.

As illustrated, the program code 4520 stored on medium 4518 and/ormemory 4516 may include a configuration data module 4602 that that whenimplemented by the one or more processors 4504 configures the one ormore processors 4504 to transmit configuration data to the UE via theexternal interface 4506, and/or to receive configuration data from anetwork node via the external interface 4506. The configuration datacomprising information for fixed cells and fixed tracking areas inwireless coverage of the communications satellite and associated withthe serving PLMN, wherein the fixed cells and the fixed tracking areasare defined as fixed geographic areas and wherein the fixed cells andthe fixed tracking area are defined independently of each other.

The program code 4520 stored on medium 4518 and/or memory 4516 mayinclude a position module 4604 that when implemented by the one or moreprocessors 4504 configures the one or more processors 4504 to receive aposition for the UE, via the external interface 4506.

The program code 4520 stored on medium 4518 and/or memory 4516 mayinclude a position transmit module 4606 that when implemented by the oneor more processors 4504 configures the one or more processors 4504 totransmit the position of the UE to a network entity, via the externalinterface 4506.

The program code 4520 stored on medium 4518 and/or memory 4516 mayinclude a service operation module 4608 that when implemented by the oneor more processors 4504 configures the one or more processors 4504 toenable a service operation, e.g., WEA, LI or EN, for the UE by a servingcore network for the serving PLMN based on at least one of the fixedserving cell and the fixed serving tracking area, e.g., using theexternal interface 4506.

The program code 4520 stored on medium 4518 and/or memory 4516 mayinclude a fixed cell and TA module 4610 that when implemented by the oneor more processors 4504 configures the one or more processors 4504 todetermine a fixed serving cell and a fixed serving tracking area inwhich the UE is located based on the position of the UE and theconfiguration information for the fixed cells and the fixed trackingareas.

The program code 4520 stored on medium 4518 and/or memory 4516 mayinclude a PLMN identifier module 4612 that when implemented by the oneor more processors 4504 configures the one or more processors 4504 togenerate a unique PLMN identifier for the fixed serving cell using thecell identifier for the fixed serving cell and the color code for thefixed serving tracking area in which the UE is located, wherein theservice operation is performed based on the unique PLMN identifier.

The program code 4520 stored on medium 4518 and/or memory 4516 mayinclude a registration request module 4614 that when implemented by theone or more processors 4504 configures the one or more processors 4504to receive a Non-Access Stratum (NAS) Registration Request message fromthe UE via the SV and a satellite NodeB (sNB), the NAS RegistrationRequest message including an indication of a fixed serving cell and afixed tracking area (TA) for the UE, which may be the identities of thefixed serving cell and fixed TA or may be the location of the UE.

The program code 4520 stored on medium 4518 and/or memory 4516 mayinclude an allowed TAs module 4616 that when implemented by the one ormore processors 4504 configures the one or more processors 4504 todetermine a plurality of allowed tracking areas (TAs) of the servingPLMN, wherein the UE is allowed to access the serving PLMN in each TA ofthe plurality of allowed TAs.

The program code 4520 stored on medium 4518 and/or memory 4516 mayinclude a registration response module 4618 that when implemented by theone or more processors 4504 configures the one or more processors 4504to send a NAS Registration Accept message to the UE via the sNB and theSV, wherein the NAS Registration Accept message includes identities anda geographic definition for the plurality of allowed TAs, and may alsoinclude identities and a geographic definition for a plurality of fixedcells of the serving PLMN. The NAS Registration Accept message may alsoinclude an indication as to whether the UE is required to perform aregistration with the serving PLMN for a change of TA after detectingthe UE is no longer in any of the plurality of allowed TAs.

The program code 4520 stored on medium 4518 and/or memory 4516 mayinclude an identify fixed cell and TA module 4620 that when implementedby the one or more processors 4504 configures the one or more processors4504 to determine the identity of the fixed serving cell and fixed TA,e.g., when NAS Registration Request message includes the location of theUE. For example, the one or more processors 4504 may be configured tomap the location to an identity of the fixed serving cell and anidentity of the fixed TA or send the location to an LMF that maps thelocation to an identity of the fixed serving cell and an identity of thefixed TA and returns the identity of the fixed serving cell and theidentity of the fixed TA to the AMF.

FIG. 47 shows a flowchart of an example procedure 4700 for supportingsatellite wireless access by a user equipment (UE) to a serving publicland mobile network (PLMN), performed by the UE, such as the UE 105 inFIGS. 1, 2, 3.

As illustrated, at block 4702 the UE receives configuration data from anetwork node via a communication satellite (e.g. an SV 102, 202 or 302),where the configuration data comprises configuration information forfixed cells and fixed tracking areas in wireless coverage of thecommunication satellite and associated with the serving PLMN, where thefixed cells and the fixed tracking areas are defined as fixed geographicareas, and where the fixed cells and the fixed tracking areas aredefined independently of each other, e.g., as discussed at stage 1 ofFIG. 22, stage 4 of FIG. 37A and for FIGS. 21A and 21B. A means forreceiving configuration data from a network node via a communicationsatellite, where the configuration data comprises configurationinformation for fixed cells and fixed tracking areas in wirelesscoverage of the communication satellite and associated with the servingPLMN, where the fixed cells and the fixed tracking areas are defined asfixed geographic areas, and where the fixed cells and the fixed trackingareas are defined independently of each other may include the satellitetransceiver 3903 and one or more processors 3904 with dedicated hardwareor implementing executable code or software instructions 3920 in inmemory 3916 and/or medium 3918, such as the configuration data module4002 in UE 3900 shown in FIGS. 39 and 40.

At block 4704, a position of the UE is obtained, where the positionenables a determination by a network entity of a fixed serving cell anda fixed serving tracking area in which the UE is located based on theposition of the UE and the configuration information for the fixed cellsand the fixed tracking areas, e.g., as discussed at stages 3, 4, and 5of FIG. 22, stages 5 and 8 of FIG. 37A, stages 3 and 9 of FIG. 37B andfor FIGS. 17-20. A means for obtaining a position of the UE, wherein theposition enables a determination by a network entity of a fixed servingcell and a fixed serving tracking area in which the UE is located basedon the position of the UE and the configuration information for thefixed cells and the fixed tracking areas may include the SPS receiver3908 or wireless transceiver 3902 and one or more processors 3904 withdedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as theposition module 4004 in UE 3900 shown in FIGS. 39 and 40.

At block 4706, a service operation is enabled for the UE by a servingcore network for the serving PLMN based on at least one of the fixedserving cell and the fixed serving tracking area, e.g., as discussed atstages 8, 9, and 10 of FIG. 22 and at stage 19 of FIG. 37A. A means forenabling a service operation for the UE by a serving core network forthe serving PLMN based on at least one of the fixed serving cell and thefixed serving tracking area may include the satellite transceiver 3903and one or more processors 3904 with dedicated hardware or implementingexecutable code or software instructions 3920 in in memory 3916 and/ormedium 3918, such as the registration module 4008, handover module 4010,EM call module 4012, WEA module 4014, in UE 3900 shown in FIGS. 39 and40.

In one implementation, each fixed cell has a cell identifier, and eachfixed tracking area has a tracking area code and a color code, whereadjacent fixed tracking areas have different color codes. In thisimplementation, the UE may generate a unique PLMN identifier for thefixed serving cell using the cell identifier for the fixed serving celland the color code for the fixed serving tracking area in which the UEis located, where the service operation is performed based on the uniquePLMN identifier, e.g., as discussed at stages 1, 8, 9, and 10 of FIG.22. In one example, the cell identifier for the each fixed cell maycomprise latitude and longitude coordinates of the UE. The latitude andlongitude coordinates may be coarsened latitude and longitudecoordinates of the UE rounded to a binary fraction of one degree. Ameans for generating a unique PLMN identifier for the fixed serving cellusing the cell identifier for the fixed serving cell and the color codefor the fixed serving tracking area in which the UE is located, whereinthe service operation is performed based on the unique PLMN identifiermay include the one or more processors 3904 with dedicated hardware orimplementing executable code or software instructions 3920 in in memory3916 and/or medium 3918, such as the PLMN identifier module 4006 in UE3900 shown in FIGS. 39 and 40.

In one implementation, the configuration information for the fixed cellsmay comprise locations of grid points in an array of grid points andcell identifiers associated with the array of grid points, where eachone grid point in the array of grid points defines one fixed cell andhas one associated cell identifier, and where the one fixed cellcomprises a coverage area of locations that are closer to a location ofthe one grid point than to a location of any other grid point in thearray of grid points, e.g., as discussed at stage 1 of FIG. 22 and forFIGS. 1 and 11. For example, the array of grid points may be arectangular array of grid points or a hexagonal array of grid points, asdiscussed for FIGS. 7 and 8.

In one implementation, the configuration information for the fixedtracking areas may comprise locations of grid points in an array of gridpoints and tracking area codes and color codes associated with the arrayof grid points, where each one grid point in the array of grid pointsdefines one fixed tracking area and has one associated tracking areacode and one associated color code, and where the one fixed trackingarea may comprise a coverage area of locations that are closer to alocation of the one grid point than to a location of any other gridpoint in the array of grid points, e.g., as discussed at stage 1 of FIG.22 and for FIG. 21. For example, the array of grid points may be arectangular array of grid points or a hexagonal array of grid points.

In one implementation, the configuration information for the fixedtracking areas may comprise locations of vertices for a plurality ofpolygons and tracking area codes and color codes associated with theplurality of polygons, where each one polygon in the array of polygonsdefines one fixed tracking area and has one associated tracking areacode and one associated color code, and where the one fixed trackingarea may be a coverage area of locations contained within the onepolygon, e.g., as discussed at stage 1 of FIG. 22 and for FIG. 21.

In one implementation, the UE may obtain the position of the UE byobtaining location measurements for downlink signals received from oneor more communication satellites (e.g. SVs 102. 202 and/or 302), one ormore Global Navigation Satellite System (GNSS) satellites (e.g., SVs190), one or more terrestrial base stations (e.g. gNBs 114) or acombination thereof, e.g., as discussed at stage 3 of FIG. 22. The UEmay determine the position based on the location measurements, e.g., asdiscussed at stage 4 of FIG. 22 and stages 3 and 5 of FIG. 37A and stage3 of FIG. 37B. A means for obtaining location measurements for downlinksignals received from one or more of communication satellites, one ormore Global Navigation Satellite System (GNSS) satellites, one or moreterrestrial base stations or a combination thereof may include the SPSreceiver 3908 or wireless transceiver 3902 shown in FIG. 39. A means fordetermining the position based on the location measurements may includethe one or more processors 3904 with dedicated hardware or implementingexecutable code or software instructions 3920 in in memory 3916 and/ormedium 3918, such as the position module 4004 in UE 3900 shown in FIGS.39 and 40.

In one implementation, the serving PLMN may be a Fifth Generation (5G)PLMN, the network node may be a satellite NodeB (e.g. sNB 106, sNB 202or sNB-CU 307), an Access and Mobility management Function (e.g. AMF122) or the communication satellite, and the network entity may be oneof the UE, the communication satellite, a serving sNB (e.g. sNB 106, sNB202 or sNB-CU 307), a serving AMF (e.g. AMF 122) or a LocationManagement Function (e.g. LMF 124).

In one implementation, the configuration data is received from thenetwork node via the communication satellite using broadcast or usingunicast, e.g., as discussed at stage 1 of FIG. 22 and stage 4 of FIG.37A and stage 2 of FIG. 37B.

In one implementation, the service operation may comprise one of aregistration of the UE with the serving core network, an emergencyservices call from the UE to a Public Safety Answering Point (PSAP),delivery of a wireless emergency alert (WEA) message to the UE, lawfulinterception for the UE, or handover of the UE within the serving PLMNor to a new serving PLMN, e.g., as discussed at stages 8-10 of FIG. 22and stage 19 of FIG. 37A.

FIG. 48 shows a flowchart of an example procedure 4800 for supportingsatellite wireless access by a user equipment (e.g. a UE 105) to aserving public land mobile network (PLMN), performed by a network nodein the PLMN, such as an sNB 106, 202 or 307, an SV 102, 202, or 302, anAMF 122, or an LMF 124.

At block 4802, configuration data is transmitted to the UE via acommunication satellite (e.g. an SV 102, 202 or 302), where theconfiguration data comprises configuration information for fixed cellsand fixed tracking areas in wireless coverage of the communicationsatellite and associated with the serving PLMN, where the fixed cellsand the fixed tracking areas are defined as fixed geographic areas, andwhere the fixed cells and the fixed tracking area are definedindependently of each other, e.g., as discussed at stage 1 of FIG. 22,stages 2 and 4 of FIG. 37A, stage 2 of FIG. 37B and for FIGS. 21A and21B. A means for transmitting configuration data to the UE via acommunication satellite, the configuration data comprising configurationinformation for fixed cells and fixed tracking areas in wirelesscoverage of the communications satellite and associated with the servingPLMN, wherein the fixed cells and the fixed tracking areas are definedas fixed geographic areas and wherein the fixed cells and the fixedtracking area are defined independently of each other may include theexternal interface 4106, the one or more processors 4104 with dedicatedhardware or implementing executable code or software instructions 4120in in memory 4116 and/or medium 4118, such as the configuration datamodule 4202 in sNB 4100 shown in FIGS. 41 and 42; the wireless interface4302, the one or more processors 4304 with dedicated hardware orimplementing executable code or software instructions 4320 in in memory4316 and/or medium 4318, such as the configuration data module 4402 inSV 4300 shown in FIGS. 43 and 44; or the external interface 4502, theone or more processors 4504 with dedicated hardware or implementingexecutable code or software instructions 4520 in in memory 4516 and/ormedium 4518, such as the configuration data module 4602 in network node4500, which may be an AMF or LMF, shown in FIGS. 45 and 46.

At block 4804, a position of the UE is received, e.g., as discussed atstage 5 of FIG. 22 and stage 7 of FIG. 37A and stage 8 of FIG. 37B. Ameans for receiving a position of the UE may include the externalinterface 4106, the one or more processors 4104 with dedicated hardwareor implementing executable code or software instructions 4120 in inmemory 4116 and/or medium 4118, such as the position module 4204 in sNB4100 shown in FIGS. 41 and 42; the wireless interface 4302, the one ormore processors 4304 with dedicated hardware or implementing executablecode or software instructions 4320 in in memory 4316 and/or medium 4318,such as the position module 4404 in SV 4300 shown in FIGS. 43 and 44; orthe external interface 4502, the one or more processors 4504 withdedicated hardware or implementing executable code or softwareinstructions 4520 in in memory 4516 and/or medium 4518, such as theposition module 4604 in network node 4500, which may be an AMF or LMF,shown in FIGS. 45 and 46.

At block 4806, the position of the UE is used to enable a determinationby a network entity of a fixed serving cell and a fixed serving trackingarea in which the UE is located based on the position of the UE and theconfiguration information for the fixed cells and the fixed trackingareas. For example, the network entity may be the network node and maydetermine the fixed serving cell and the fixed serving tracking area inwhich the UE is located at block 4806, e.g. as described for stage 5 ofFIG. 22 and stage 13 of FIG. 37A and stage 9 of FIG. 37B. Alternatively,the network node may transmit the position of the UE to the networkentity which may then determine the fixed serving cell and the fixedserving tracking area in which the UE is located based on the positionof the UE. e.g., as discussed at stage 5 of FIG. 22, stages 14-17 ofFIG. 37A and stages 11-12 of FIG. 37B. A means for using the position ofthe UE to enable a determination by a network entity of a fixed servingcell and a fixed serving tracking area in which the UE is located basedon the position of the UE and the configuration information for thefixed cells and the fixed tracking areas may include the externalinterface 4106, the one or more processors 4104 with dedicated hardwareor implementing executable code or software instructions 4120 in inmemory 4116 and/or medium 4118, such as the position transmit module4206 or fixed cell and TA module 4210 in sNB 4100 shown in FIGS. 41 and42; the wireless interface 4302, the one or more processors 4304 withdedicated hardware or implementing executable code or softwareinstructions 4320 in in memory 4316 and/or medium 4318, such as theposition transmit module 4406 or fixed cell and TA module 4410 in SV4300 shown in FIGS. 43 and 44; or the external interface 4502, the oneor more processors 4504 with dedicated hardware or implementingexecutable code or software instructions 4520 in in memory 4516 and/ormedium 4518, such as the position transmit module 4606 or fixed cell andTA module 4610 in network node 4500, which may be an AMF or LMF, shownin FIGS. 45 and 46.

At block 4808, a service operation for the UE is enabled by a servingcore network for the serving PLMN based on at least one of the fixedserving cell and the fixed serving tracking area, e.g., as discussed atstages 8, 9, or 10 of FIG. 22 and stage 19 of FIG. 37A. A means forenabling a service operation for the UE by a serving core network forthe serving PLMN based on at least one of the fixed serving cell and thefixed serving tracking area may include the external interface 4106, theone or more processors 4104 with dedicated hardware or implementingexecutable code or software instructions 4120 in in memory 4116 and/ormedium 4118, such as the service operation module 4208 in sNB 4100 shownin FIGS. 41 and 42; the wireless interface 4302, the one or moreprocessors 4304 with dedicated hardware or implementing executable codeor software instructions 4320 in in memory 4316 and/or medium 4318, suchas the service operation module 4408 in SV 4300 shown in FIGS. 43 and44; or the external interface 4502, the one or more processors 4504 withdedicated hardware or implementing executable code or softwareinstructions 4520 in in memory 4516 and/or medium 4518, such as theservice operation module 4608 in network node 4500, which may be an AMFor LMF, shown in FIGS. 45 and 46.

In one implementation, each fixed cell has a cell identifier, each fixedtracking area has a tracking area code and a color code, where adjacentfixed tracking areas have different color codes, and a unique PLMNidentifier can be generated for the fixed serving cell using the cellidentifier for the fixed serving cell and the color code for the fixedserving tracking area in which the UE is located, where the serviceoperation can be performed based on the unique PLMN identifier, e.g., asdiscussed at stages 1, 8, 9, or 10 of FIG. 22 and for FIGS. 21A and 21B.For example, the cell identifier for the each fixed cell may compriselatitude and longitude coordinates of the UE. The latitude and longitudecoordinates may be coarsened latitude and longitude coordinates of theUE rounded to a binary fraction of one degree.

In one implementation, the configuration information for the fixed cellsmay comprise locations of grid points in an array of grid points andcell identifiers associated with the array of grid points, where eachone grid point in the array of grid points defines one fixed cell andhas one associated cell identifier, and where the one fixed cell may bea coverage area of locations that are closer to a location of the onegrid point than to a location of any other grid point in the array ofgrid points, e.g., as discussed at stage 1 of FIG. 22 and for FIGS. 7and 11. For example, the array of grid points may be a rectangular arrayof grid points or a hexagonal array of grid points.

In one implementation, the configuration information for the fixedtracking areas may comprise locations of grid points in an array of gridpoints and tracking area codes and color codes associated with the arrayof grid points, where each one grid point in the array of grid pointsdefines one fixed tracking area and has one associated tracking areacode and one associated color code, and where the one fixed trackingarea may be a coverage area of locations that are closer to a locationof the one grid point than to a location of any other grid point in thearray of grid points, e.g., as discussed at stage 1 of FIG. 22 and forFIG. 21. For example, the array of grid points may be a rectangulararray of grid points or a hexagonal array of grid points.

In one implementation, the configuration information for the fixedtracking areas may comprise locations of vertices for a plurality ofpolygons and tracking area codes and color codes associated with theplurality of polygons, where each one polygon in the array of polygonsdefines one fixed tracking area and has one associated tracking areacode and one associated color code, and where the one fixed trackingarea may be a coverage area of locations contained within the onepolygon, e.g., as discussed at stage 1 of FIG. 22 and for FIG. 21.

In one implementation, the position of the UE may be determined by theUE based on location measurements for downlink signals received by theUE from one or more of communication satellites (e.g. SVs 102, 202and/or 302), one or more Global Navigation Satellite System (GNSS)satellites (e.g. SVs 190), one or more terrestrial base stations (e.g.gNBs 114) or a combination thereof, e.g., as discussed at stage 4 ofFIG. 22 and stage 5 of FIG. 37A and stage 5 of FIG. 37B.

In one implementation, the serving PLMN may be a Fifth Generation (5G)PLMN, where the network node may be a satellite NodeB (e.g. sNB 106, sNB202 or sNB-CU 307), an Access and Mobility management Function (e.g. AMF122) or the communication satellite, and where the network entity may beone of the UE, the communication satellite, the network node, a servingAMF (e.g. AMF 122) or a Location Management Function (e.g. LMF 124).

In one implementation, the configuration data may be transmitted to theUE via the communication satellite using broadcast or using unicast,e.g., as discussed at stage 1 of FIG. 22 and stages 2 and 4 of FIG. 37Aand stage 2 of FIG. 37B.

In one implementation, the service operation may be one of aregistration of the UE with the serving core network, an emergencyservices call from the UE to a Public Safety Answering Point (PSAP),delivery of a wireless emergency alert (WEA) message to the UE, lawfulinterception for the UE, or handover of the UE within the serving PLMNor to a new serving PLMN, e.g., as discussed at stages 8-10 of FIG. 22and stage 19 of FIG. 37A.

FIG. 49 shows a flowchart of an example procedure 4900 for supportingsatellite wireless access by a user equipment (e.g. a UE 105) to aserving public land mobile network (PLMN), performed by a network entityin the serving PLMN, which may be an AMF 122 or LMF 124.

At block 4902, configuration data is sent to the UE, where theconfiguration data comprises configuration information for fixed cellsand fixed tracking areas in wireless coverage of a communicationssatellite being accessed by the UE (e.g. an SV 102, 202 or 302) andassociated with the serving PLMN, where the fixed cells and the fixedtracking areas are defined as fixed geographic areas and where the fixedcells and the fixed tracking areas are defined independently of eachother, e.g., as discussed at stage 1 of FIG. 22, stage 18 of FIG. 37A,stage 13 of FIG. 37B and for FIGS. 21A and 21B. A means for sendingconfiguration data to the UE, wherein the configuration data comprisesconfiguration information for fixed cells and fixed tracking areas inwireless coverage of a communications satellite being accessed by the UEand associated with the serving PLMN, wherein the fixed cells and thefixed tracking areas are defined as fixed geographic areas and whereinthe fixed cells and the fixed tracking area are defined independently ofeach other may include the external interface 4502, the one or moreprocessors 4504 with dedicated hardware or implementing executable codeor software instructions 4520 in in memory 4516 and/or medium 4518, suchas the configuration data module 4602 in in network node 4500, which maybe an AMF or LMF, shown in FIGS. 45 and 46.

At block 4904, a position of the UE is obtained (e.g. is received fromthe UE or is determined by the network entity), e.g., as discussed atstage 14 of FIG. 37A and stage 11 of FIG. 37B. A means for obtaining aposition of the UE may include the external interface 4502, the one ormore processors 4504 with dedicated hardware or implementing executablecode or software instructions 4520 in in memory 4516 and/or medium 4518,such as the position module 4604 in in network node 4500, which may bean AMF or LMF, shown in FIGS. 45 and 46.

At block 4906, a fixed serving cell and a fixed serving tracking area inwhich the UE is located are determined based on the position of the UEand the configuration information for the fixed cells and the fixedtracking areas, e.g., as discussed at stage 5 of FIG. 22 and stages14-17 of FIG. 37A and stage 12 of FIG. 37B. A means for determining afixed serving cell and a fixed serving tracking area in which the UE islocated based on the position of the UE and the configurationinformation for the fixed cells and the fixed tracking areas may includethe external interface 4502, the one or more processors 4504 withdedicated hardware or implementing executable code or softwareinstructions 4520 in in memory 4516 and/or medium 4518, such as thefixed cell and TA module 4608 in in network node 4500, which may be anAMF or LMF, shown in FIGS. 45 and 46.

At block 4908, a service operation is enabled for the UE by a servingcore network for the serving PLMN based on at least one of the fixedserving cell and the fixed serving tracking area, e.g., as discussed atstages 8, 9, or 10 of FIG. 22 and stage 19 of FIG. 37A. A means forenabling a service operation for the UE by a serving core network forthe serving PLMN based on at least one of the fixed serving cell and thefixed serving tracking area may include the external interface 4502, theone or more processors 4504 with dedicated hardware or implementingexecutable code or software instructions 4520 in in memory 4516 and/ormedium 4518, such as the service operation module 4608 in in networknode 4500, which may be an AMF or LMF, shown in FIGS. 45 and 46.

In one implementation, each fixed cell has a cell identifier, and eachfixed tracking area has a tracking area code and a color code, whereadjacent fixed tracking areas have different color codes, and thenetwork entity may generate a unique PLMN identifier for the fixedserving cell using the cell identifier for the fixed serving cell andthe color code for the fixed serving tracking area in which the UE islocated, where the service operation can be performed based on theunique PLMN identifier, e.g., as discussed at stage 5 of FIG. 22 and forFIG. 21. For example, the cell identifier for the each fixed cell maycomprise latitude and longitude coordinates of the UE. The latitude andlongitude coordinates may comprise coarsened latitude and longitudecoordinates of the UE rounded to a binary fraction of one degree. Ameans for generating a unique PLMN identifier for the fixed serving cellusing the cell identifier for the fixed serving cell and the color codefor the fixed serving tracking area in which the UE is located, whereinthe service operation is performed based on the unique PLMN identifiermay include the external interface 4502, the one or more processors 4504with dedicated hardware or implementing executable code or softwareinstructions 4520 in in memory 4516 and/or medium 4518, such as the PLMNidentifier module 4612 in in network node 4500, which may be an AMF orLMF, shown in FIGS. 45 and 46.

In one implementation, the configuration information for the fixed cellsmay comprise locations of grid points in an array of grid points andcell identifiers associated with the array of grid points, where eachone grid point in the array of grid points defines one fixed cell andhas one associated cell identifier, and where the one fixed cell may bea coverage area of locations that are closer to a location of the onegrid point than to a location of any other grid point in the array ofgrid points, e.g., as discussed at stage 1 of FIG. 22 and for FIGS. 7and 11. For example, the array of grid points may be a rectangular arrayof grid points or a hexagonal array of grid points.

In one implementation, the configuration information for the fixedtracking areas may be locations of grid points in an array of gridpoints and tracking area codes and color codes associated with the arrayof grid points, where each one grid point in the array of grid pointsdefines one fixed tracking area and has one associated tracking areacode and one associated color code, and where the one fixed trackingarea may be a coverage area of locations that are closer to a locationof the one grid point than to a location of any other grid point in thearray of grid points, e.g., as discussed at stage 1 of FIG. 22 and forFIG. 21. For example, the array of grid points may be a rectangulararray of grid points or a hexagonal array of grid points.

In one implementation, the configuration information for the fixedtracking areas may be locations of vertices for a plurality of polygonsand tracking area codes and color codes associated with the plurality ofpolygons, where each one polygon in the array of polygons defines onefixed tracking area and has one associated tracking area code and oneassociated color code, and where the one fixed tracking area may be acoverage area of locations contained within the one polygon, e.g., asdiscussed at stage 1 of FIG. 22 and for FIG. 21.

In one implementation, the position of the UE is determined (e.g. by theUE) based on location measurements for downlink signals received by theUE from one or more communication satellites (e.g. SVs 102. 202 and/or302), one or more Global Navigation Satellite System (GNSS) satellites(e.g. SVs 114), one or more terrestrial base stations (e.g. gNBs 114) ora combination thereof, e.g., as discussed at stage 4 of FIG. 22 andstage 14 of FIG. 37A.

In one implementation, the serving PLMN may be a Fifth Generation (5G)PLMN, and the network entity may be a serving AMF for the UE (e.g. AMF122) or a Location Management Function (e.g. LMF 124).

In one implementation, the service operation may be one of aregistration of the UE with the serving PLMN, an emergency services callfrom the UE to a Public Safety Answering Point (PSAP), delivery of awireless emergency alert (WEA) message to the UE, lawful interceptionfor the UE, or handover of the UE within the serving PLMN or to a newserving PLMN, e.g., as discussed at stages 8, 9, or 10 of FIG. 22 andstage 19 of FIG. 37A.

FIG. 50 shows a flowchart of an example procedure 5000 performed by afirst network node for transferring signaling for a first plurality ofradio cells from a first earth station to a second earth station, wherethe first plurality of radio cells is supported by a space vehicle (e.g.an SV 102, 202 or 302). The first network node, for example, may be thesNB 106, sNB 202, sNB-DU 302 or sNB-CU 307.

As illustrated, at block 5002, first signaling is transported between afirst plurality of User Equipments (e.g. UEs 105) and a Core Network(e.g. 5GCN 110) at a first time, where the first signaling istransported via the SV, the first earth station and the first networknode, and wherein the first signaling is transported between the SV andthe first plurality of UEs using the first plurality of radio cells,e.g., as discussed in reference to FIGS. 23-27, stage 1 of FIGS. 30 and31, and FIGS. 32 and 33. A means for transporting first signalingbetween a first plurality of User Equipments (UEs) and a Core Network ata first time, wherein the first signaling is transported via the SV, thefirst earth station and the first network node, and wherein the firstsignaling is transported between the SV and the first plurality of UEsusing the first plurality of radio cells may include the externalinterface 4106, sNB-DU 4112, sNB-CU 4114, the one or more processors4104 with dedicated hardware or implementing executable code or softwareinstructions 4120 in in memory 4116 and/or medium 4118, such as thetransport signaling module 4214 in sNB 4100 shown in FIGS. 41 and 42.

At block 5004, the first network node ceases to transport the firstsignaling between the first plurality of UEs and the Core Network at asecond time, where the second time is subsequent to the first time,e.g., as discussed in reference to FIGS. 23-27, stages 3-4 of FIGS. 30and 31, and FIGS. 32 and 33. A means for ceasing to transport the firstsignaling between the first plurality of UEs and the Core Network at asecond time, wherein the second time is subsequent to the first time mayinclude the external interface 4106, sNB-DU 4112, sNB-CU 4114, the oneor more processors 4104 with dedicated hardware or implementingexecutable code or software instructions 4120 in in memory 4116 and/ormedium 4118, such as the handover module 4216 in sNB 4100 shown in FIGS.41 and 42.

At block 5006, the transport of second signaling between the firstplurality of UEs and the Core Network is enabled after the second timevia the SV, the second earth station and a second network node, wherethe second signaling is transported between the SV and the firstplurality of UEs using the first plurality of radio cells, as discussedin reference to FIGS. 23, 24, 26, 27, stages 5-7 of FIGS. 30 and 31, andFIGS. 32 and 33. A means for enabling the transport of second signalingbetween the first plurality of UEs and the Core Network after the secondtime via the SV, the second earth station and a second network node,wherein the second signaling is transported between the SV and the firstplurality of UEs using the first plurality of radio cells may includethe external interface 4106, sNB-DU 4112, sNB-CU 4114, the one or moreprocessors 4104 with dedicated hardware or implementing executable codeor software instructions 4120 in in memory 4116 and/or medium 4118, suchas the transport signaling module 4214 in sNB 4100 shown in FIGS. 41 and42.

In one implementation, the first signaling and the second signalingcomprise user plane signaling and control plane signaling, where theuser plane signaling includes signaling for data and voice connectionsbetween each of the plurality of UEs and external entities, and wherethe control plane signaling includes signaling for connections andassociations between each of the plurality of UEs and entities in theCore Network, as discussed in reference to FIGS. 23-35.

In one implementation, each radio cell in the first plurality of radiocells comprises one or more radio beams supported by the SV, asdiscussed in reference to FIG. 4.

In one implementation, the first network node and the second networknode may be a same satellite NodeB (e.g. an sNB 106), where the firstsignaling and the second signaling are transported via the SV in atransparent mode, e.g., as discussed in reference to FIG. 1 and FIGS.23-25. Enabling the transport of the second signaling between theplurality of UEs and the Core Network after the second time may thencomprise at least one of: (i) determining a timing for each radio cellin the first plurality of radio cells, where the timing is applicableafter the second time, and providing the timing of a serving radio cellin the first plurality of radio cells to each UE in the first pluralityof UEs before the second time; or (ii) determining a timing advance foreach UE in the first plurality of UEs, where the timing advance isapplicable after the second time, and providing the timing advance toeach UE in the first plurality of UEs before the second time; or acombination thereof, e.g., as discussed in reference to FIGS. 23-25 andimplementations I3, I3 and I5. A means for determining a timing for eachradio cell in the first plurality of radio cells, wherein the timing isapplicable after the second time, and providing the timing of a servingradio cell in the first plurality of radio cells to each UE in the firstplurality of UEs before the second time may include the externalinterface 4106, sNB-DU 4112, sNB-CU 4114, the one or more processors4104 with dedicated hardware or implementing executable code or softwareinstructions 4120 in in memory 4116 and/or medium 4118, such as thetiming module 4218 in sNB 4100 shown in FIGS. 41 and 42. A means fordetermining a timing advance for each UE in the first plurality of UEs,wherein the timing advance is applicable after the second time, andproviding the timing advance to each UE in the first plurality of UEsbefore the second time may include the external interface 4106, sNB-DU4112, sNB-CU 4114, the one or more processors 4104 with dedicatedhardware or implementing executable code or software instructions 4120in in memory 4116 and/or medium 4118, such as the timing advance module4220 in sNB 4100 shown in FIGS. 41 and 42.

In one implementation, determining the timing for each radio cell in thefirst plurality of radio cells is based on (i) a known orbital positionof the SV, and (ii) known or measured propagation and transmissiondelays for: signaling links between the sNB and the first earth station,signaling links between the first earth station and the SV; signalinglinks between the sNB and the second earth station; signaling linksbetween the second earth station and the SV; and signaling links betweenthe SV and the first plurality of UEs, e.g., as discussed in referenceto FIGS. 23-25 and implementation I3.

In one implementation, referred to a “regenerative implementation”, thefirst network node and the second network node may be a same satelliteNode B (e.g. an sNB 202), where the sNB is included within the SV, andwhere the first signaling and the second signaling are transported viathe SV in a regenerative mode, e.g., as discussed in reference to FIG. 2and FIGS. 26-31. In the regenerative implementation, the first earthstation and the second earth station may act as Level 1 relays, andenabling the transport of the second signaling between the plurality ofUEs and the Core Network after the second time may comprisetransferring, at the second time, a plurality of data links from thefirst earth station to the second earth station, where each data link inthe plurality of data links may be a Level 2 connection between the sNBand the core network, and where signaling for each data link in theplurality of data links is transported through the first earth stationat a Level 1 prior to the second time and is transported through thesecond earth station at a Level 1 after the second time, e.g., asdiscussed in reference to FIG. 30. A means for transferring, at thesecond time, a plurality of data links from the first earth station tothe second earth station, wherein each data link in the plurality ofdata links comprises a Level 2 connection between the sNB and the corenetwork, and wherein signaling for each data link in the plurality ofdata links is transported through the first earth station at a Level 1prior to the second time and is transported through the second earthstation at a Level 1 after the second time may include the externalinterface 4106, sNB-DU 4112, sNB-CU 4114, the one or more processors4104 with dedicated hardware or implementing executable code or softwareinstructions 4120 in in memory 4116 and/or medium 4118, such as the datalink transfer module 4222 in sNB 4100 shown in FIGS. 41 and 42.

Alternatively in the regenerative implementation, the first earthstation and the second earth station may act as Level 2 relays, whereenabling the transport of the second signaling between the plurality ofUEs and the Core Network after the second time may comprise: (i)releasing, immediately prior to the second time, a first plurality ofdata links between the sNB and the core network, where the firstplurality of data links transports the first signaling, and where eachdata link in the first plurality of data links may comprise a Level 2connection between the sNB and the first earth station and aconcatenated Level 2 connection between the first earth station and thecore network; (ii) transferring, at the second time and from the firstearth station to the second earth station, a Level 1 transport ofsignaling between the sNB and the core network; and (iii) establishing,immediately after the second time, a second plurality of data linksbetween the sNB and the core network, where the second plurality of datalinks transports the second signaling, where each data link in thesecond plurality of data links may comprise a Level 2 connection betweenthe sNB and the second earth station and a concatenated Level 2connection between the second earth station and the core network, andwhere each data link in the second plurality of data links correspondsto one data link in the first plurality of data links, e.g., asdiscussed in reference to FIG. 31. A means for releasing, immediatelyprior to the second time, a first plurality of data links between thesNB and the core network, wherein the first plurality of data linkstransports the first signaling, and wherein each data link in the firstplurality of data links comprises a Level 2 connection between the sNBand the first earth station and a concatenated Level 2 connectionbetween the first earth station and the core network may include theexternal interface 4106, sNB-DU 4112, sNB-CU 4114, the one or moreprocessors 4104 with dedicated hardware or implementing executable codeor software instructions 4120 in in memory 4116 and/or medium 4118, suchas the release module 4224 in sNB 4100 shown in FIGS. 41 and 42. A meansfor transferring, at the second time and from the first earth station tothe second earth station, a Level 1 transport of signaling between thesNB and the core network may include the external interface 4106, sNB-DU4112, sNB-CU 4114, the one or more processors 4104 with dedicatedhardware or implementing executable code or software instructions 4120in in memory 4116 and/or medium 4118, such as the transfer module 4226in sNB 4100 shown in FIGS. 41 and 42. A means for establishing,immediately after the second time, a second plurality of data linksbetween the sNB and the core network, wherein the second plurality ofdata links transports the second signaling, wherein each data link inthe second plurality of data links comprises a Level 2 connectionbetween the sNB and the second earth station and a concatenated Level 2connection between the second earth station and the core network, andwherein each data link in the second plurality of data links correspondsto one data link in the first plurality of data links may include theexternal interface 4106, sNB-DU 4112, sNB-CU 4114, the one or moreprocessors 4104 with dedicated hardware or implementing executable codeor software instructions 4120 in in memory 4116 and/or medium 4118, suchas the establish module 4228 in sNB 4100 shown in FIGS. 41 and 42.

In one implementation, referred to as a “regenerative implementationwith split architecture”, the SV is used in a regenerative mode with asplit architecture, where the SV (e.g. an sNB 302) includes a satelliteNodeB (sNB) Distributed Unit (such as sNB-DU 302), where the sNB-DUcommunicates with a first sNB Central Unit (e.g. an sNB-CU 307-1) totransport the first signaling and with a second sNB-CU (e.g. an sNB-CU307-2) to transport the second signaling, where the first signaling istransported between the sNB-DU and the core network via the firstsNB-CU, and where the second signaling is transported between the sNB-DUand the core network via the second sNB-CU, e.g., as discussed inreference to FIG. 3 and FIGS. 32-36.

In one aspect of the regenerative implementation with splitarchitecture, referred to as Aspect A1, the first sNB-CU may be thesecond sNB-CU, the first network node may be the second network node,and the first network node may be the sNB-DU or the first sNB-CU, e.g.,as discussed in reference to FIG. 32.

In Aspect A1, the first earth station and the second earth station mayact as Level 1 relays, where enabling the transport of the secondsignaling between the plurality of UEs and the Core Network after thesecond time may comprise transferring, at the second time, a pluralityof data links from the first earth station to the second earth station,where each data link in the plurality of data links may be a Level 2connection between the first network node and the other of the sNB-DUand the first sNB-CU, where each data link in the plurality of datalinks is transported through the first earth station at a Level 1 priorto the second time and is transported through the second earth stationat a Level 1 after the second time, e.g., as discussed in reference toFIGS. 30 and 32. A means for transferring, at the second time, aplurality of data links from the first earth station to the second earthstation, wherein each data link in the plurality of data links comprisesa Level 2 connection between the first network node and the other of thesNB-DU and the first sNB-CU, wherein each data link in the plurality ofdata links is transported through the first earth station at a Level 1prior to the second time and is transported through the second earthstation at a Level 1 after the second time may include the externalinterface 4106, sNB-DU 4112, sNB-CU 4114, the one or more processors4104 with dedicated hardware or implementing executable code or softwareinstructions 4120 in in memory 4116 and/or medium 4118, such as the datalink transfer module 4222 in sNB 4100 shown in FIGS. 41 and 42.

In Aspect A1, the first earth station and the second earth station mayalternatively act as a Level 2 relays, where enabling the transport ofthe second signaling between the first plurality of UEs and the CoreNetwork after the second time may comprise: (i) releasing, immediatelyprior to the second time, a first plurality of data links between thefirst network node and the other of the sNB-DU and the first sNB-CU,where the first plurality of data links transports the first signaling,and where each data link in the first plurality of data links maycomprise a Level 2 connection between the first network node and thefirst earth station and a concatenated Level 2 connection between thefirst earth station and the other of the sNB-DU and the first sNB-CU;(ii) transferring, at the second time and from the first earth stationto the second earth station, a Level 1 transport of signaling betweenthe first network node and the other of the sNB-DU and the first sNB-CU;and (iii) establishing, immediately after the second time, a secondplurality of data links between the first network node and the other ofthe sNB-DU and the first sNB-CU, where the second plurality of datalinks transports the second signaling, where each data link in thesecond plurality of data links may comprise a Level 2 connection betweenthe first network node and the second earth station and a concatenatedLevel 2 connection between the second earth station and the other of thesNB-DU and the first sNB-CU, and where each data link in the secondplurality of data links corresponds to one data link in the firstplurality of data links, e.g., as discussed in reference to FIGS. 31 and32. A means for releasing, immediately prior to the second time, a firstplurality of data links between the first network node and the other ofthe sNB-DU and the first sNB-CU, wherein the first plurality of datalinks transports the first signaling, and wherein each data link in thefirst plurality of data links comprises a Level 2 connection between thefirst network node and the first earth station and a concatenated Level2 connection between the first earth station and the other of the sNB-DUand the first sNB-CU may include the external interface 4106, sNB-DU4112, sNB-CU 4114, the one or more processors 4104 with dedicatedhardware or implementing executable code or software instructions 4120in in memory 4116 and/or medium 4118, such as the release module 4224 insNB 4100 shown in FIGS. 41 and 42. A means for transferring, at thesecond time and from the first earth station to the second earthstation, a Level 1 transport of signaling between the first network nodeand the other of the sNB-DU and the first sNB-CU may include theexternal interface 4106, sNB-DU 4112, sNB-CU 4114, the one or moreprocessors 4104 with dedicated hardware or implementing executable codeor software instructions 4120 in in memory 4116 and/or medium 4118, suchas the transfer module 4226 in sNB 4100 shown in FIGS. 41 and 42. Ameans for establishing, immediately after the second time, a secondplurality of data links between the first network node and the other ofthe sNB-DU and the first sNB-CU, wherein the second plurality of datalinks transports the second signaling, wherein each data link in thesecond plurality of data links comprises a Level 2 connection betweenthe first network node and the second earth station and a concatenatedLevel 2 connection between the second earth station and the other of thesNB-DU and the first sNB-CU, and wherein each data link in the secondplurality of data links corresponds to one data link in the firstplurality of data links may include the external interface 4106, sNB-DU4112, sNB-CU 4114, the one or more processors 4104 with dedicatedhardware or implementing executable code or software instructions 4120in in memory 4116 and/or medium 4118, such as the establish module 4228in sNB 4100 shown in FIGS. 41 and 42.

In another aspect of the regenerative implementation with splitarchitecture, referred to as Aspect A2, the first sNB-CU is differentthan the second sNB-CU, and the process may further include enabling thetransport of the second signaling between the first plurality of UEs andthe Core Network after the second time via the SV by performing amodified handover procedure for each UE in the first plurality of UEs,where either (i) the first network node may be the first sNB-CU and thesecond network node may be the second sNB-CU, or (ii) the first networknode and the second network node each may be the sNB-DU, e.g., asdiscussed in reference to FIGS. 33-36. A means for enabling thetransport of the second signaling between the first plurality of UEs andthe Core Network after the second time via the SV by performing amodified handover procedure for each UE in the first plurality of UEs,wherein either (i) the first network node comprises the first sNB-CU andthe second network node comprises the second sNB-CU, or (ii) the firstnetwork node and the second network node each comprise the sNB-DU mayinclude the external interface 4106, sNB-DU 4112, sNB-CU 4114, the oneor more processors 4104 with dedicated hardware or implementingexecutable code or software instructions 4120 in in memory 4116 and/ormedium 4118, such as the handover module 4216 in sNB 4100 shown in FIGS.41 and 42.

In Aspect A2, performing the modified handover procedure for each UE inthe first plurality of UEs may comprise at least one of: (i) releasingfirst non-UE associated links and connections between the sNB-DU and thefirst sNB-CU immediately before the second time, where signaling for thefirst non-UE associated links and connections is transported between thesNB-DU and the first sNB-CU via the first earth station at a Level 1 ora Level 2; (ii) establishing second non-UE associated links andconnections between the sNB-DU and the second sNB-CU immediately afterthe second time, where signaling for the second non-UE associated linksand connections is transported between the sNB-DU and the second sNB-CUvia the second earth station at a Level 1 or a Level 2; (iii) releasingfirst UE associated connections and tunnels between the sNB-DU, thefirst sNB-CU and the core network immediately before the second time,where signaling for the first UE associated connections and tunnels istransported between the sNB-DU and the first sNB-CU using the firstnon-UE associated links and connections; (iv) establishing second UEassociated connections and tunnels between the sNB-DU, the second sNB-CUand the core network immediately after the second time, where signalingfor the second UE associated connections and tunnels is transportedbetween the sNB-DU and the second sNB-CU via the second earth stationusing the second non-UE associated links and connections; or (v) acombination of these, e.g., as discussed in reference to FIGS. 33-35. Ameans for releasing first non-UE associated links and connectionsbetween the sNB-DU and the first sNB-CU immediately before the secondtime, wherein signaling for the first non-UE associated links andconnections is transported between the sNB-DU and the first sNB-CU viathe first earth station at a Level 1 or a Level 2 may include theexternal interface 4106, sNB-DU 4112, sNB-CU 4114, the one or moreprocessors 4104 with dedicated hardware or implementing executable codeor software instructions 4120 in in memory 4116 and/or medium 4118, suchas the release module 4224 in sNB 4100 shown in FIGS. 41 and 42. A meansfor establishing second non-UE associated links and connections betweenthe sNB-DU and the second sNB-CU immediately after the second time,wherein signaling for the second non-UE associated links and connectionsis transported between the sNB-DU and the second sNB-CU via the secondearth station at a Level 1 or a Level 2 may include the externalinterface 4106, sNB-DU 4112, sNB-CU 4114, the one or more processors4104 with dedicated hardware or implementing executable code or softwareinstructions 4120 in in memory 4116 and/or medium 4118, such as theestablish module 4228 in sNB 4100 shown in FIGS. 41 and 42. A means forreleasing first UE associated connections and tunnels between thesNB-DU, the first sNB-CU and the core network immediately before thesecond time, wherein signaling for the first UE associated connectionsand tunnels is transported between the sNB-DU and the first sNB-CU usingthe first non-UE associated links and connections may include theexternal interface 4106, sNB-DU 4112, sNB-CU 4114, the one or moreprocessors 4104 with dedicated hardware or implementing executable codeor software instructions 4120 in in memory 4116 and/or medium 4118, suchas the release module 4224 in sNB 4100 shown in FIGS. 41 and 42. A meansfor establishing second UE associated connections and tunnels betweenthe sNB-DU, the second sNB-CU and the core network immediately after thesecond time, wherein signaling for the second UE associated connectionsand tunnels is transported between the sNB-DU and the second sNB-CU viathe second earth station using the second non-UE associated links andconnections may include the external interface 4106, sNB-DU 4112, sNB-CU4114, the one or more processors 4104 with dedicated hardware orimplementing executable code or software instructions 4120 in in memory4116 and/or medium 4118, such as the establish module 4228 in sNB 4100shown in FIGS. 41 and 42.

In Aspect A2, the first non-UE associated links and connections and thesecond non-UE associated links and connections may each include use ofone or more of an Internet Protocol (IP), a User Datagram Protocol (UDP)and a Stream Control Transmission Protocol (SCTP), e.g., as discussed inreference to FIGS. 34-35.

In Aspect A2, the first UE associated connections and tunnels and thesecond UE associated connections and tunnels may each include use of oneor more of a GPRS Tunneling Protocol (GTP), an F1 Application Protocol(F1AP), a Packet Data Convergence Protocol (PDCP), a Service DataProtocol (SDAP), a Radio Resource Control (RRC) protocol, a NextGeneration Application Protocol (NGAP) and/or an NR User Plane Protocol(NRUPP), e.g., as discussed in reference to FIGS. 34-35.

In one implementation, the process may further include: (i) transportingthird signaling between a second plurality of UEs and the Core Networkat the first time, where the third signaling is transported via the SV,the first earth station and the first network node, where the thirdsignaling is transported between the SV and the second plurality of UEsusing a second plurality of radio cells; and (ii) handing over thesecond plurality of UEs before the second time to a third plurality ofradio cells supported by one or more SVs different from the SV, wherefourth signaling is transported between the second plurality of UEs andthe Core Network after the second time, and where the fourth signalingis transported via the one or more SVs using the third plurality ofradio cells, e.g., as discussed in reference to FIGS. 23-27, and FIGS.32 and 33. A means for transporting third signaling between a secondplurality of UEs and the Core Network at the first time, wherein thethird signaling is transported via the SV, the first earth station andthe first network node, wherein the third signaling is transportedbetween the SV and the second plurality of UEs using a second pluralityof radio cells may include the external interface 4106, sNB-DU 4112,sNB-CU 4114, the one or more processors 4104 with dedicated hardware orimplementing executable code or software instructions 4120 in in memory4116 and/or medium 4118, such as the transport signaling module 4214 insNB 4100 shown in FIGS. 41 and 42. A means for handing over the secondplurality of UEs before the second time to a third plurality of radiocells supported by one or more SVs different from the SV, wherein fourthsignaling is transported between the second plurality of UEs and theCore Network after the second time, and wherein the fourth signaling istransported via the one or more SVs using the third plurality of radiocells may include the external interface 4106, sNB-DU 4112, sNB-CU 4114,the one or more processors 4104 with dedicated hardware or implementingexecutable code or software instructions 4120 in in memory 4116 and/ormedium 4118, such as the handover module 4216 in sNB 4100 shown in FIGS.41 and 42.

FIG. 51 shows a flowchart of an example procedure 5100 performed by auser equipment (e.g. the UE 105 of FIGS. 1-3) for supporting access bythe UE via a space vehicle (e.g. an SV 102. 202 or 302) to a servingPublic Land Mobile Network (PLMN).

At block 5102, the UE obtains a country of the UE, where the country ofthe UE is based on a location of the UE, e.g., as discussed at stages 5,9 and 10 of FIG. 37A and stages 3 and 10 of FIG. 37B. A means forobtaining a country of the UE, wherein the country of the UE is based ona location of the UE may include the satellite transceiver 3903 and oneor more processors 3904 with dedicated hardware or implementingexecutable code or software instructions 3920 in in memory 3916 and/ormedium 3918, such as the country module 4016 in UE 3900 shown in FIGS.39 and 40.

At block 5104, one or more first radio cells available to the UE aredetected, where each of the one or more first radio cells comprises oneor more radio beams transmitted from one or more first SVs (e.g. SVs102, 202 and/or 302), e.g., as discussed at stage 2 of FIG. 37A andstage 2 of FIG. 37B. A means for detecting one or more first radio cellsavailable to the UE, wherein each of the one or more first radio cellscomprises one or more radio beams transmitted from one or more first SVsmay include the satellite transceiver 3903 and one or more processors3904 with dedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as thedetect radio cells 4018 in UE 3900 shown in FIGS. 39 and 40.

At block 5106, identities of supported PLMNs broadcast in the one ormore first radio cells are received, where the identity of eachsupported PLMN indicates a country for the each supported PLMN, e.g., asdiscussed at stage 2 of FIG. 37A and stage 2 of FIG. 37B. A means forreceiving identities of supported PLMNs broadcast in the one or morefirst radio cells, wherein the identity of each supported PLMN indicatesa country for the each supported PLMN may include the satellitetransceiver 3903 and one or more processors 3904 with dedicated hardwareor implementing executable code or software instructions 3920 in inmemory 3916 and/or medium 3918, such as the supported PLMNs module 4020in UE 3900 shown in FIGS. 39 and 40.

At block 5108, the serving PLMN is selected, where the serving PLMN is aPLMN for the country of the UE, and where the serving PLMN is includedin the supported PLMNs, e.g., as discussed at stage 11 of FIG. 37A andstage 7 of FIG. 37B. A means for selecting the serving PLMN, wherein theserving PLMN is a PLMN for the country of the UE, and wherein theserving PLMN is included in the supported PLMNs may include thesatellite transceiver 3903 and one or more processors 3904 withdedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as theselect PLMN module 4022 in UE 3900 shown in FIGS. 39 and 40.

At block 5110, a first radio cell of the one or more first radio cellsavailable to the UE is selected, where the first radio cell supports theserving PLMN, e.g., as discussed at stage 6 of FIG. 37A and stage 4 ofFIG. 37B. A means for selecting a first radio cell of the one or morefirst radio cells available to the UE, wherein the first radio cellsupports the serving PLMN may include the satellite transceiver 3903 andone or more processors 3904 with dedicated hardware or implementingexecutable code or software instructions 3920 in in memory 3916 and/ormedium 3918, such as the select radio cell module 4024 in UE 3900 shownin FIGS. 39 and 40.

At block 5112, the serving PLMN is accessed using the first radio cell,e.g., as discussed at stages 12-19 of FIG. 37A and stages 8-14 of FIG.37B. A means for accessing the serving PLMN using the first radio cellmay include the satellite transceiver 3903 and one or more processors3904 with dedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as the PLMNaccess module 4026 in UE 3900 shown in FIGS. 39 and 40.

In one implementation, the serving PLMN may be a Fifth Generation (5G)Core Network (e.g. 5GCN 110).

In one implementation, the identity of each PLMN of the supported PLMNsbroadcast in the one or more first radio cells may be a mobile countrycode (MCC) and a mobile network code (MNC), where the MCC indicates thecountry for the each PLMN, e.g., as discussed at stage 2 of FIG. 37A andstage 2 of FIG. 37B.

In one implementation, accessing the serving PLMN comprises exchangingsignaling with the serving PLMN via the SV and a first satellite NodeB(e.g. an sNB 106, 202 or 307), e.g., as discussed at stages 12-19 ofFIG. 37A and stages 8-14 of FIG. 37B. A means for accessing the servingPLMN using the first radio cell may include the satellite transceiver3903 and one or more processors 3904 with dedicated hardware orimplementing executable code or software instructions 3920 in in memory3916 and/or medium 3918, such as the PLMN access module 4026 in UE 3900shown in FIGS. 39 and 40.

In one implementation, obtaining the country of the UE may includeselecting a second radio cell of the one or more first radio cellsavailable to the UE based on the second radio cell supporting apreferred PLMN for the UE, e.g., as discussed at stage 6 of FIG. 37A andstage 4 of FIG. 37B. A means for selecting a second radio cell of theone or more first radio cells available to the UE based on the secondradio cell supporting a preferred PLMN for the UE may include thesatellite transceiver 3903 and one or more processors 3904 withdedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as theselect radio cell module 4024 in UE 3900 shown in FIGS. 39 and 40. Usingthe second radio cell, a request may be sent to a second sNB (e.g. ansNB 106, 202 or 307) to access a PLMN, e.g. as discussed at stage 7 ofFIG. 37A and stage 5 of FIG. 37B. A means for sending, using the secondradio cell, a request to a second sNB to access a PLMN may include thesatellite transceiver 3903 and one or more processors 3904 withdedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as the PLMNaccess module 4026 in UE 3900 shown in FIGS. 39 and 40. The country ofthe UE may then be received from the second sNB, e.g., as discussed atstages 9 and 10 of FIG. 37A and stage 10 of FIG. 37B. A means forreceiving the country of the UE from the second sNB may include thesatellite transceiver 3903 and one or more processors 3904 withdedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as thecountry module 4016 in UE 3900 shown in FIGS. 39 and 40. The second sNB,for example, may determine the location of the UE based on a coveragearea of the second radio cell or a coverage area for a radio beam of thesecond radio cell, where the radio beam is used by the UE to send therequest to the second sNB, e.g., as discussed at stage 8 of FIG. 37A andstage 9 of FIG. 37B. Additionally, the UE may obtain locationmeasurements, where the location measurements include measurements ofsignals received from the one or more first SVs (e.g. SVs 102, 202 or302), signals received from navigation SVs (e.g. SVs 190), or both typesof signals, e.g., as discussed at stage 3 of FIG. 37A. A means forobtaining location measurements, wherein the location measurementsinclude measurements of signals received from the one or more first SVs,signals received from navigation SVs, or both types of signals mayinclude the satellite transceiver 3903 and the SPS receiver 3908. The UEmay determine the location of the UE based on the location measurements,e.g., as discussed at stage 5 of FIG. 37A and stage 3 of FIG. 37B. Ameans for determining the location of the UE based on the locationmeasurements may include the one or more processors 3904 with dedicatedhardware or implementing executable code or software instructions 3920in in memory 3916 and/or medium 3918, such as the position module 4004in UE 3900 shown in FIGS. 39 and 40. The UE may then send the locationof the UE to the second sNB as part of the request to access the PLMN,e.g., as discussed at stage 7 of FIG. 37A and stage 8 of FIG. 37B. Ameans for sending the location of the UE to the second sNB as part ofthe request to access the PLMN may include the satellite transceiver3903 and one or more processors 3904 with dedicated hardware orimplementing executable code or software instructions 3920 in in memory3916 and/or medium 3918, such as the PLMN access module 4026 in UE 3900shown in FIGS. 39 and 40. The UE may also receive security informationfrom the second sNB, cipher the location of the UE based on the securityinformation, and send the ciphered location of the UE to the second sNBas part of the request to access the PLMN, e.g. as described for stages6 and 8 of FIG. 37B. A means for receiving security information from thesecond sNB, a means for ciphering the location of the UE based on thesecurity information, and a means for sending the ciphered location ofthe UE to the second sNB as part of the request to access the PLMN mayinclude the satellite transceiver 3903 and one or more processors 3904with dedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as the PLMNaccess module 4026 in UE 3900 shown in FIGS. 39 and 40. The UE may sendthe request to access the PLMN to the second sNB in a Radio ResourceControl (RRC) Setup Request message or an RRC Setup Complete message andmay receive the country of the UE from the second sNB in an RRC Setupmessage or an RRC Reject message, e.g., as discussed at stages 7, 9 and10 of FIG. 37A and stages 8 and 10 of FIG. 37B. In one example, thefirst sNB may be the second sNB, and the first radio cell may be thesecond radio cell.

In one implementation, obtaining the country of the UE may compriseobtaining location measurements, where the location measurements includemeasurements of signals received from the one or more first SVs (e.g.SVs 102, 202 or 302), signals received from navigation SVs (e.g. SVs190), or both types of signals, e.g., as discussed at stage 3 of FIG.37A and stage 3 of FIG. 37B. A means for obtaining locationmeasurements, wherein the location measurements include measurements ofsignals received from the one or more first SVs, signals received fromnavigation SVs, or both types of signals may include the satellitetransceiver 3903 and the SPS receiver 3908. The location of the UE maybe determined based on the location measurements, e.g., as discussed atstage 5 of FIG. 37A and stage 3 of FIG. 37B. A means for determining thelocation of the UE based on the location measurements may include theone or more processors 3904 with dedicated hardware or implementingexecutable code or software instructions 3920 in in memory 3916 and/ormedium 3918, such as the position module 4004 in UE 3900 shown in FIGS.39 and 40. Location related information for the supported PLMNs may bereceived broadcast in the one or more radio cells, e.g., as discussed atstage 4 of FIG. 37A. A means for receiving location related informationfor the supported PLMNs broadcast in the one or more radio cells mayinclude the satellite transceiver 3903 and one or more processors 3904with dedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as thesupported PLMNs module 4020 in UE 3900 shown in FIGS. 39 and 40. Thecountry of the UE may be determined based on the location relatedinformation and the location of the UE, e.g., as discussed at stage 5 ofFIG. 37A and stage 3 of FIG. 37B. A means for determining the country ofthe UE based on the location related information and the location of theUE may include the one or more processors 3904 with dedicated hardwareor implementing executable code or software instructions 3920 in inmemory 3916 and/or medium 3918, such as the country module 4016 in UE3900 shown in FIGS. 39 and 40. In this implementation, the locationrelated information for each supported PLMN may comprise geographicdefinition for fixed cells of the each supported PLMN, geographicdefinition for fixed tracking areas of the each supported PLMN, or both.

In one implementation, accessing the serving PLMN comprises exchangingsignaling with the serving PLMN via the SV and a first sNB (e.g. an sNB106, 202 or 307), and sending a Non-Access Stratum (NAS) RegistrationRequest message to a network node for the serving PLMN and receiving aNAS Registration Accept from the network node, e.g., as discussed atstages 12 and 18 of FIG. 37A and stages 8 and 13 of FIG. 37B. A meansfor exchanging signaling with the serving PLMN via the SV and a firstsatellite NodeB (sNB) and a means for sending a Non-Access Stratum (NAS)Registration Request message to a network node for the serving PLMN andreceiving a NAS Registration Accept from the network node may includethe satellite transceiver 3903 and one or more processors 3904 withdedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as the PLMNaccess module 4026 and the registration module 4028 in UE 3900 shown inFIGS. 39 and 40. For example, the network node may be an Access andMobility management Function (e.g. an AMF 122). In one example, sendingthe NAS Registration Request message to the network node may comprisessending a Radio Resource Control (RRC) Setup Complete message to thefirst sNB via the SV, where the RRC Setup Complete message includes theNAS Registration Request message and indicates the serving PLMN, e.g.,as discussed at stage 12 of FIG. 37A and stage 8 of FIG. 37B. In oneexample, referred to as example E1, the NAS Registration Accept messagemay include identities and location information for a plurality ofallowed (e.g. fixed) tracking areas (TAs) of the serving PLMN, where theUE is allowed to access the serving PLMN in each TA of the plurality ofallowed TAs, e.g., as discussed at stages 18-20 of FIG. 37A and stages13 and 14 of FIG. 37B. The NAS Registration Accept message, for example,may also include identities and a geographic definition for a pluralityof fixed cells of the serving PLMN, e.g., as discussed at stage 18 ofFIG. 37A and stage 13 of FIG. 37B. In one example, accessing the servingPLMN may include determining a current location of the UE, e.g., asdiscussed at stage 5 of FIG. 22 and stage 19 of FIG. 37A. A means fordetermining a current location of the UE may include the satellitetransceiver 3903 and one or more processors 3904 with dedicated hardwareor implementing executable code or software instructions 3920 in inmemory 3916 and/or medium 3918, such as the position module 4004 in UE3900 shown in FIGS. 39 and 40. The current location may be mapped to atleast one of an allowed TA of the plurality of allowed TAs, a fixed cellof the plurality of fixed cells, or a combination thereof, based on thegeographic definition for the plurality of allowed TAs, the geographicdefinition for the plurality of fixed cells or a combination thereof,e.g., as discussed at stage 5 of FIG. 22 and stage 19 of FIG. 37A. Ameans for mapping the current location to at least one of an allowed TAof the plurality of allowed TAs, a fixed cell of the plurality of fixedcells, or a combination thereof, based on the geographic definition forthe plurality of allowed TAs, the geographic definition for theplurality of fixed cells or a combination thereof may include thesatellite transceiver 3903 and one or more processors 3904 withdedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as the PLMNaccess module 4026 in UE 3900 shown in FIGS. 39 and 40. At least one ofan indication of the allowed TA, an indication of the fixed cell or acombination thereof may be included in a message sent to the servingPLMN, where the at least one of the indication of the allowed TA, theindication of the fixed cell or the combination thereof enable a servicefor the UE by the serving PLMN, e.g., as discussed at stages 6-11 ofFIG. 22 and stage 19 of FIG. 37A.

In one aspect of Example E1 above, referred to as Aspect A3, the UE mayfurther detect one or more second radio cells available to the UE, whereeach of the one or more second radio cells comprises one or more radiobeams transmitted from one or more second SVs (e.g. SVs 102, 202 and/or302), where each of the one or more second radio cells indicates supportfor the serving PLMN, e.g., as discussed at stage 20 of FIG. 37A. Ameans for detecting one or more second radio cells available to the UE,wherein each of the one or more second radio cells comprises one or moreradio beams transmitted from one or more second SVs, wherein each of theone or more second radio cells indicates support for the serving PLMNmay include the satellite transceiver 3903 and one or more processors3904 with dedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as thedetect radio cells module 4018 in UE 3900 shown in FIGS. 39 and 40.Identities of a plurality of supported TAs of the serving PLMN may bereceived broadcast in the one or more second radio cells, e.g., asdiscussed at stage 20 of FIG. 37A. A means for receiving identities of aplurality of supported TAs of the serving PLMN broadcast in the one ormore second radio cells may include the satellite transceiver 3903 andone or more processors 3904 with dedicated hardware or implementingexecutable code or software instructions 3920 in in memory 3916 and/ormedium 3918, such as the supported PLMNs module 4020 in UE 3900 shown inFIGS. 39 and 40. The UE may determine whether the UE is required toperform a registration with the serving PLMN for a change of TA, basedat least in part on the plurality of allowed TAs and the plurality ofsupported TAs, e.g., as discussed at stage 20 of FIG. 37A and followingstage 14 of FIG. 37B. A means for determining whether the UE is requiredto perform a registration with the serving PLMN for a change of TA,based at least in part on the plurality of allowed TAs and the pluralityof supported TAs may include the one or more processors 3904 withdedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as theregistration module 4028 in UE 3900 shown in FIGS. 39 and 40. The UE mayperform the registration with the serving PLMN for the change of TAusing one of the one or more second radio cells when the UE determinesthe UE is required to perform the registration with the serving PLMN forthe change of TA, e.g., as discussed at stage 21 of FIG. 37A andfollowing stage 14 of FIG. 37B. A means for performing the registrationwith the serving PLMN for the change of TA using one of the one or moresecond radio cells when the UE determines the UE is required to performthe registration with the serving PLMN for the change of TA may includethe satellite transceiver 3903 and one or more processors 3904 withdedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as theregistration module 4028 in UE 3900 shown in FIGS. 39 and 40. The UE maycamp on the one of the one or more second radio cells without performingthe registration with the serving PLMN for the change of TA, when the UEis in an idle state and when the UE determines the UE is not required toperform the registration with the serving PLMN for the change of TA,e.g., as discussed at stage 21 of FIG. 37A and following stage 14 ofFIG. 37B. A means for camping on the one of the one or more second radiocells without performing the registration with the serving PLMN for thechange of TA, when the UE is in an idle state and when the UE determinesthe UE is not required to perform the registration with the serving PLMNfor the change of TA may include the satellite transceiver 3903 and oneor more processors 3904 with dedicated hardware or implementingexecutable code or software instructions 3920 in in memory 3916 and/ormedium 3918, such as the registration module 4028 in UE 3900 shown inFIGS. 39 and 40. The UE may access the serving PLMN using the one of theone or more second radio cells without performing the registration withthe serving PLMN for the change of TA, when the UE is in a connectedstate and when the UE determines the UE is not required to perform theregistration with the serving PLMN for the change of TA, e.g., asdiscussed at stage 21 of FIG. 37A and following stage 14 of FIG. 37B. Ameans for accessing the serving PLMN using the one of the one or moresecond radio cells without performing the registration with the servingPLMN for the change of TA, when the UE is in a connected state and whenthe UE determines the UE is not required to perform the registrationwith the serving PLMN for the change of TA may include the satellitetransceiver 3903 and one or more processors 3904 with dedicated hardwareor implementing executable code or software instructions 3920 in inmemory 3916 and/or medium 3918, such as the registration module 4028 inUE 3900 shown in FIGS. 39 and 40.

For Aspect A3, the UE may determine that the UE is required to performthe registration with the serving PLMN for the change of TA bydetermining that the plurality of supported TAs do not include any TA ofthe plurality of allowed TAs, e.g., as discussed at stage 20 of FIG. 37Aand following stage 14 of FIG. 37B.

For Aspect A3, the UE may determine that the UE is not required toperform the registration with the serving PLMN for the change of TA bydetermining that the plurality of supported TAs includes at least one ofthe plurality of allowed TAs, where the one of the one or more secondradio cells indicates support for the at least one of the plurality ofallowed TAs, e.g., as discussed at stage 20 of FIG. 37A and followingstage 14 of FIG. 37B. For example, determining that the UE is notrequired to perform the registration with the serving PLMN for thechange of TA may further comprise determining that the NAS RegistrationAccept message includes an indication allowing the UE to access theserving PLMN using a radio cell supporting at least one of the pluralityof allowed TAs when the UE is not located in any of the plurality ofallowed TAs, e.g., as discussed at stage 20 of FIG. 37A and followingstage 14 of FIG. 37B.

In one implementation of Aspect A3, determining whether the UE isrequired to perform the registration for the change of TA with theserving PLMN may further comprise determining a current location of theUE, e.g., as discussed at stage 20 of FIG. 37A. A means for determininga current location of the UE may include the SPS receiver 3908,satellite transceiver 3903 and one or more processors 3904 withdedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as theposition module 4004 in UE 3900 shown in FIGS. 39 and 40. The UE maydetermine whether the current location of the UE is inside any allowedTA of the plurality of allowed TAs, e.g., as discussed at stage 20 ofFIG. 37A. A means for determining whether the current location of the UEis inside any allowed TA of the plurality of allowed TAs may include thesatellite transceiver 3903 and one or more processors 3904 withdedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as theregistration module 4028 in UE 3900 shown in FIGS. 39 and 40. The UE maydetermine that the UE is required to perform the registration for thechange of TA with the serving PLMN when the current location of the UEis not inside the any allowed TA or when the current location of the UEis inside the any allowed TA and the any allowed TA is not included inthe plurality of supported TAs, e.g., as discussed at stage 20 of FIG.37A and following stage 14 of FIG. 37B. A means for determining that theUE is required to perform the registration for the change of TA with theserving PLMN when the current location of the UE is not inside the anyallowed TA or when the current location of the UE is inside the anyallowed TA and the any allowed TA is not included in the plurality ofsupported TAs may include the satellite transceiver 3903 and one or moreprocessors 3904 with dedicated hardware or implementing executable codeor software instructions 3920 in in memory 3916 and/or medium 3918, suchas the registration module 4028 in UE 3900 shown in FIGS. 39 and 40. TheUE may determine that the UE is not required to perform the registrationfor the change of TA with the serving PLMN when the current location ofthe UE is inside the any allowed TA and when the any allowed TA isincluded in the plurality of supported TAs, and where the one of the oneor more second radio cells indicates support for the any allowed TA,e.g., as discussed at stage 20 of FIG. 37A and following stage 14 ofFIG. 37B. A means for determining that the UE is not required to performthe registration for the change of TA with the serving PLMN when thecurrent location of the UE is inside the any allowed TA and when the anyallowed TA is included in the plurality of supported TAs, and whereinthe one of the one or more second radio cells indicates support for theany allowed TA may include the satellite transceiver 3903 and one ormore processors 3904 with dedicated hardware or implementing executablecode or software instructions 3920 in in memory 3916 and/or medium 3918,such as the registration module 4028 in UE 3900 shown in FIGS. 39 and40. For example, determining whether the UE is required to perform theregistration for the change of TA with the serving PLMN may furtherinclude determining whether the NAS Registration Accept message includesan indication (e.g. a Registration flag) requiring the UE to perform theregistration for the change of TA with the serving PLMN when the UE isnot located inside the any of the plurality of allowed TAs, e.g., asdiscussed at stages 18-20 of FIG. 37A and stages 13 and 14 of FIG. 37B.A means for determining whether the UE is required to perform theregistration for the change of TA with the serving PLMN furthercomprises determining whether the NAS Registration Accept messageincludes an indication requiring the UE to perform the registration forthe change of TA with the serving PLMN when the UE is not located insidethe any of the plurality of allowed TAs may include the satellitetransceiver 3903 and one or more processors 3904 with dedicated hardwareor implementing executable code or software instructions 3920 in inmemory 3916 and/or medium 3918, such as the registration module 4028 inUE 3900 shown in FIGS. 39 and 40.

FIG. 52 shows a flowchart of an example procedure 5200 performed by asatellite Node B (e.g. an sNB 106, sNB 202 or sNB-CU 307) for supportingaccess by a user equipment (e.g. the UE 105 of FIGS. 1-3) via a spacevehicle (e.g. an SV 102. 202 or 302) to a serving Public Land MobileNetwork (PLMN).

At block 5202, the sNB controls the SV to broadcast system informationblocks (SIBs) in each of one or more radio cells of the sNB, where theSIBs in each of the one or more radio cells of the sNB includeidentities of supported PLMNs for the sNB, and where the identity ofeach supported PLMN indicates a country for the each supported PLMN,e.g., e.g., as discussed at stage 2 of FIG. 37A and stage 2 of FIG. 37B.A means for controlling the SV to broadcast system information blocks(SIBs) in each of one or more radio cells of the sNB, wherein the SIBsin each of the one or more radio cells of the sNB include identities ofsupported PLMNs for the sNB, and wherein the identity of each supportedPLMN indicates a country for the each supported PLMN may include theexternal interface 4106 and one or more processors 4104 with dedicatedhardware or implementing executable code or software instructions 4120in in memory 4116 and/or medium 4118, such as the SIB (supported PLMNs)module 4230 in sNB 4100 shown in FIGS. 41 and 42.

At block 5204, a request to access a PLMN is received from the UE viaone of the one or more radio cells of the sNB, e.g., as discussed atstage 7 of FIG. 37A and stage 8 of FIG. 37B. A means for receiving arequest to access a PLMN from the UE via one of the one or more radiocells of the sNB may include the external interface 4106 and one or moreprocessors 4104 with dedicated hardware or implementing executable codeor software instructions 4120 in in memory 4116 and/or medium 4118, suchas the PLMN access request module 4232 in sNB 4100 shown in FIGS. 41 and42.

At block 5206, a location of the UE is obtained, e.g., as discussed atstages 7 and 8 of FIG. 37A and stages 8 and 9 of FIG. 37B. A means forobtaining a location of the UE may include the external interface 4106and one or more processors 4104 with dedicated hardware or implementingexecutable code or software instructions 4120 in in memory 4116 and/ormedium 4118, such as the country module 4234 in sNB 4100 shown in FIGS.41 and 42.

At block 5208, a country of the UE is determined based on the location,e.g., as discussed at stage 8 of FIG. 37A and stage 9 of FIG. 37B. Ameans for determining a country of the UE based on the location mayinclude the external interface 4106 and one or more processors 4104 withdedicated hardware or implementing executable code or softwareinstructions 4120 in in memory 4116 and/or medium 4118, such as thecountry module 4234 in sNB 4100 shown in FIGS. 41 and 42.

At block 5210, an indication of the country of the UE is sent to the UE,where the indication of the country of the UE assists the UE to selectthe serving PLMN from the supported PLMNs based on the serving PLMNbeing for the country of the UE, e.g., as discussed at stages 9-11 ofFIG. 37A and stage 10 of FIG. 37B. A means for sending an indication ofthe country of the UE to the UE, wherein the indication of the countryof the UE assists the UE to select the serving PLMN from the supportedPLMNs based on the serving PLMN being for the country of the UE mayinclude the external interface 4106 and one or more processors 4104 withdedicated hardware or implementing executable code or softwareinstructions 4120 in in memory 4116 and/or medium 4118, such as the PLMNaccess response module 4236 in sNB 4100 shown in FIGS. 41 and 42.

In one implementation, the SV is used in a transparent mode, aregenerative mode with a non-split architecture or in a regenerativemode with a split architecture, where the sNB is terrestrial (e.g. ansNB 106) when the SV is used in the transparent mode, where the sNB ispart of the SV (e.g. an sNB 202) when the SV is used in the regenerativemode with the non-split architecture, and where the sNB is terrestrialand comprises an sNB Central Unit (e.g. an sNB-CU 307) when the SV isused in the regenerative mode with the split architecture, e.g., asdiscussed in FIGS. 1, 2, and 3.

In one implementation, the identity of each PLMN of the supported PLMNsbroadcast in the one or more radio cells comprises a mobile country code(MCC) and a mobile network code (MNC), where the MCC indicates thecountry for the each PLMN, e.g., as discussed at stage 2 of FIG. 37A andstage 2 of FIG. 37B.

In one implementation, the indication of the country of the UE comprisesan MCC.

In one implementation, the location of the UE may be obtained byreceiving the location of the UE from the UE in the request to accessthe PLMN, e.g., as discussed at stage 7 of FIG. 37A and stage 5 of FIG.37B. A means for obtaining the location of the UE by receiving thelocation of the UE from the UE in the request to access the PLMN mayinclude the external interface 4106 and one or more processors 4104 withdedicated hardware or implementing executable code or softwareinstructions 4120 in in memory 4116 and/or medium 4118, such as thecountry module 4234 in sNB 4100 shown in FIGS. 41 and 42. In thisimplementation, security information may be sent to the UE, where thelocation received from the UE is ciphered by the UE based on thesecurity information, and the location received from the UE may bedeciphered by the sNB, e.g. as described for stages 6 and 8 of FIG. 37B.The security information may be sent to the UE in a broadcast SIB, e.g.as described for stage 2 of FIG. 37B. A means for sending securityinformation to the UE, wherein the location received from the UE isciphered based on the security information, a means for deciphering thelocation, and a means for sending the security information to the UE ina broadcast SIB, may include the external interface 4106 and one or moreprocessors 4104 with dedicated hardware or implementing executable codeor software instructions 4120 in in memory 4116 and/or medium 4118, suchas the SIB (supported PLMNs) module 4230 and the country module 4234 insNB 4100 shown in FIGS. 41 and 42.

In one implementation, the location of the UE may be obtained bydetermining the location based on a coverage area of the one of the oneor more radio cells of the sNB or a coverage area for a radio beam ofthe one of the one or more radio cells of the sNB, where the radio beamis used by the UE to send the request to access the PLMN to the sNB,e.g., as discussed at stage 8 of FIG. 37A and stage 9 of FIG. 37B. Ameans for obtaining the location of the UE by determining the locationbased on a coverage area of the one of the one or more radio cells ofthe sNB or a coverage area for a radio beam of the one of the one ormore radio cells of the sNB, wherein the radio beam is used by the UE tosend the request to access the PLMN to the sNB may include the externalinterface 4106 and one or more processors 4104 with dedicated hardwareor implementing executable code or software instructions 4120 in inmemory 4116 and/or medium 4118, such as the country module 4234 in sNB4100 shown in FIGS. 41 and 42.

In one implementation, the request to access the PLMN may be receivedfrom the UE in a Radio Resource Control (RRC) Setup Request message oran RRC Setup Complete message, where the indication of the country ofthe UE is sent to the UE in an RRC Setup message or an RRC Rejectmessage, e.g., as discussed at stages 7, 9, and 10 of FIG. 37A andstages 8 and 10 of FIG. 37B. The sNB may further determine whether thecountry of the UE is supported by the sNB, e.g., as discussed at stage 8of FIG. 37A and stage 9 of FIG. 37B. A means for determining whether thecountry of the UE is supported by the sNB may include the externalinterface 4106 and one or more processors 4104 with dedicated hardwareor implementing executable code or software instructions 4120 in inmemory 4116 and/or medium 4118, such as the PLMN access response module4236 in sNB 4100 shown in FIGS. 41 and 42. The indication of the countryof the UE may be sent to the UE when the country of the UE is notsupported by the sNB, e.g., as discussed at stage 9 of FIG. 37A andstage 10 of FIG. 37B. A means for sending the RRC Setup message when thecountry of the UE is supported by the sNB and a means for sending theRRC Reject message when the country of the UE is not supported by thesNB may include the external interface 4106 and one or more processors4104 with dedicated hardware or implementing executable code or softwareinstructions 4120 in in memory 4116 and/or medium 4118, such as the PLMNaccess response module 4236 in sNB 4100 shown in FIGS. 41 and 42.

In one implementation, the sNB may additionally receive a first messagefrom the UE, where the first message includes a second message and anindication of a selected PLMN, e.g., as discussed at stage 12 of FIG.37A and stage 8 of FIG. 37B. A third message may be sent to a firstnetwork node in the selected PLMN, where the third message includes thesecond message and an indication of a fixed serving cell and a fixedtracking area (TA) for the UE, e.g., as discussed at stage 14 of FIG.37A and stage 11 of FIG. 37B. A means for receiving a first message fromthe UE, wherein the first message includes a second message and anindication of a selected PLMN and a means for sending a third message toa first network node in the selected PLMN, wherein the third messageincludes the second message and an indication of a fixed serving celland a fixed tracking area (TA) for the UE may include the externalinterface 4106 and one or more processors 4104 with dedicated hardwareor implementing executable code or software instructions 4120 in inmemory 4116 and/or medium 4118, such as the registration module 4238 insNB 4100 shown in FIGS. 41 and 42. The first network node, for example,may be an Access and Mobility management Function (e.g. an AMF 122). Theindication of the fixed serving cell and the fixed TA for the UE maycomprise the location of the UE, where a second network node in theserving PLMN maps the location of the UE to the fixed serving cell andthe fixed TA, e.g., as discussed at stages 13, 14, 15, and 16 of FIG.37A and stages 11 and 12 of FIG. 37B. The second network node may be theAMF or a Location Management Function (e.g. LMF 124), e.g., as discussedat stages 14, 15, and 16 of FIG. 37A and stage 12 of FIG. 37B. The sNBmay map the location of the UE to an identity of the fixed serving celland an identity of the fixed TA, where the indication of the fixedserving cell and the fixed TA for the UE comprises the identity of thefixed serving cell and the identity of the fixed TA, e.g., as discussedat stage 13 of FIG. 37A and stage 9 of FIG. 37B. A means for mapping thelocation of the UE to an identity of the fixed serving cell and anidentity of the fixed TA, wherein the indication of the fixed servingcell and the fixed TA for the UE comprises the identity of the fixedserving cell and the identity of the fixed TA may include the one ormore processors 4104 with dedicated hardware or implementing executablecode or software instructions 4120 in in memory 4116 and/or medium 4118,such as the registration module 4238 in sNB 4100 shown in FIGS. 41 and42.

The first message may be an RRC Setup Complete message, the secondmessage may be a Non Access Stratum (NAS) Registration Request messageand the third message may be a Next Generation Application Protocol(NGAP) Initial UE message, e.g., as discussed at stages 12 and 14 ofFIG. 37A and stages 8 and 11 of FIG. 37B.

FIG. 53 shows a flowchart of an example procedure 5300 performed by anAccess and Mobility management Function (e.g. an AMF 122) for supportingaccess by a user equipment (e.g. the UE 105 in FIGS. 1-3) via a spacevehicle (e.g. an SV 102, 202 or 302) to a serving Public Land MobileNetwork (PLMN).

At block 5302, a Non-Access Stratum (NAS) Registration Request messageis received from the UE via the SV and a satellite NodeB (e.g. an sNB106, sNB 202 or sNB-CU 307), where the NAS Registration Request messageis received with an indication of a fixed serving cell and a fixedtracking area (TA) for the UE, e.g., as discussed at stage 14 of FIG.37A and stage 11 of FIG. 37B. A means for receiving a Non-Access Stratum(NAS) Registration Request message from the UE via the SV and asatellite NodeB (sNB), wherein the NAS Registration Request message isreceived with an indication of a fixed serving cell and a fixed trackingarea (TA) for the UE may include the external interface 4502, the one ormore processors 4504 with dedicated hardware or implementing executablecode or software instructions 4520 in in memory 4516 and/or medium 4518,such as the registration request module 4614 in AMF 4500, shown in FIGS.45 and 46.

At block 5304, a plurality of allowed tracking areas (TAs) of theserving PLMN is determined, where the UE is allowed to access theserving PLMN in each TA of the plurality of allowed TAs, e.g., e.g., asdiscussed at stage 17 of FIG. 37A and stage 13 of FIG. 37B. A means fordetermining a plurality of allowed tracking areas (TAs) of the servingPLMN, wherein the UE is allowed to access the serving PLMN in each TA ofthe plurality of allowed TAs may include the external interface 4502,the one or more processors 4504 with dedicated hardware or implementingexecutable code or software instructions 4520 in in memory 4516 and/ormedium 4518, such as the allowed TAs module 4616 in AMF 4500, shown inFIGS. 45 and 46.

At block 5306, a NAS Registration Accept message is sent to the UE viathe sNB and the SV, wherein the NAS Registration Accept message includesidentities and a geographic definition for the plurality of allowed TAs,e.g., as discussed at stage 18 of FIG. 37A and stage 13 of FIG. 37B. Ameans for sending a NAS Registration Accept message to the UE via thesNB and the SV, wherein the NAS Registration Accept message includesidentities and a geographic definition for the plurality of allowed TAsmay include the external interface 4502, the one or more processors 4504with dedicated hardware or implementing executable code or softwareinstructions 4520 in in memory 4516 and/or medium 4518, such as theregistration response module 4618 in AMF 4500, shown in FIGS. 45 and 46.

In one implementation, identities and a geographic definition for aplurality of fixed cells of the serving PLMN may be included in the NASRegistration Accept message sent to the UE, e.g., as discussed at stage18 of FIG. 37A and stage 13 of FIG. 37B. The plurality of fixed cells ofthe serving PLMN, for example, may comprise fixed cells belonging to theplurality of allowed TAs, e.g., as discussed at stage 18 of FIG. 37A andstage 13 of FIG. 37B.

In one implementation, the NAS Registration Accept message may includean indication (e.g. a Registration flag) as to whether or not the UE isrequired to perform a registration with the serving PLMN for a change ofTA after detecting the UE is no longer in any of the plurality ofallowed TAs, e.g., as discussed at stage 18 of FIG. 37A and stage 13 ofFIG. 37B.

In one implementation, the indication of the fixed serving cell and thefixed TA for the UE may be an identity of the fixed serving cell and anidentity of the fixed TA, e.g., as discussed at stage 14 of FIG. 37A andstage 13 of FIG. 37B.

In one implementation, the indication of the fixed serving cell and thefixed TA for the UE may be a location of the UE. The AMF may then mapthe location to an identity of the fixed serving cell and an identity ofthe fixed TA, e.g., as discussed at stage 17 of FIG. 37A. A means formapping the location to an identity of the fixed serving cell and anidentity of the fixed TA may include the one or more processors 4504with dedicated hardware or implementing executable code or softwareinstructions 4520 in in memory 4516 and/or medium 4518, such as theidentify fixed cell and TA module 4620 in AMF 4500, shown in FIGS. 45and 46. Alternatively, the AMF may send the location of the UE to aLocation Management Function (e.g. an LMF 124), where the LMF maps thelocation of the UE to an identity of the fixed serving cell and anidentity of the fixed TA, and where the LMF returns the identity of thefixed serving cell and the identity of the fixed TA to the AMF, e.g., asdiscussed at stages 15 and 16 of FIG. 37A. A means for sending thelocation of the UE to a Location Management Function (LMF), wherein theLMF maps the location of the UE to an identity of the fixed serving celland an identity of the fixed TA, wherein the LMF returns the identity ofthe fixed serving cell and the identity of the fixed TA to the AMF mayinclude the one or more processors 4504 with dedicated hardware orimplementing executable code or software instructions 4520 in in memory4516 and/or medium 4518, such as the identify fixed cell and TA module4620 in AMF 4500, shown in FIGS. 45 and 46.

FIG. 54 shows a flowchart of an example procedure 5400 performed by asatellite Node B (e.g. an sNB 106, sNB 202 or sNB-CU-307) to assistwireless access by user equipments (e.g. including UE 105 in FIGS. 1-3)to serving Public Land Mobile Networks (PLMNs) via space vehicles (e.g.SVs 102, 202 and/or 302).

At block 5402, a remaining lifetime for a radio cell controlled by thesNB is determined, where the remaining lifetime is an amount of timeuntil a change of the radio cell, e.g., as discussed at stage 5 of FIG.38. A means for determining a remaining lifetime for a radio cellcontrolled by the sNB, wherein the remaining lifetime is an amount oftime until a change of the radio cell may include the external interface4106 and one or more processors 4104 with dedicated hardware orimplementing executable code or software instructions 4120 in in memory4116 and/or medium 4118, such as the lifetime module 4240 in sNB 4100shown in FIGS. 41 and 42.

At block 5404, a system information block (SIB) is generated indicatingthe remaining lifetime of the radio cell, e.g., as discussed at stage 6of FIG. 38. A means for generating a system information block (SIB)indicating the remaining lifetime of the radio cell may include theexternal interface 4106 and one or more processors 4104 with dedicatedhardware or implementing executable code or software instructions 4120in in memory 4116 and/or medium 4118, such as the SIB module 4244 in sNB4100 shown in FIGS. 41 and 42.

At block 5406, the SIB is broadcast in the radio cell using an SV (e.g.an SV 102, 202 or 302) for the radio cell, e.g., as discussed at stage 6of FIG. 38. A means for broadcasting the SIB in the radio cell using anSV for the radio cell may include the external interface 4106 and one ormore processors 4104 with dedicated hardware or implementing executablecode or software instructions 4120 in in memory 4116 and/or medium 4118,such as the provide lifetime/TA module 4246 in sNB 4100 shown in FIGS.41 and 42.

In one implementation, the SV may be used in a transparent mode, aregenerative mode with a non-split architecture or in a regenerativemode with a split architecture, e.g., as discussed in FIGS. 1-3. The sNBmay be terrestrial (e.g. an sNB 106) when the SV is used in thetransparent mode. The sNB may be part of the SV (e.g. an sNB 202) whenthe SV is used in the regenerative mode with the non-split architecture.The sNB may be terrestrial and may comprise an sNB Central Unit (e.g.may be an sNB-CU 307) when the SV is used in the regenerative mode withthe split architecture.

In one implementation, the change of the radio cell may comprise atleast one of: a change of an earth station (e.g. an ES 104) used by thesNB to exchange signaling for the radio cell with either the SV for theradio cell (e.g. when the sNB comprises an sNB 106 or sNB-CU 307) orwith a 5G Core Network (e.g. when the sNB comprises an sNB 202); achange in timing for the radio cell; a change in carrier frequency forthe radio cell; a change in bandwidth for the radio cell; a change incoverage area for the radio cell; a change to radio beams used by theradio cell; a change in a cell identity (ID) for the radio cell; acessation of support by the radio cell for one or more tracking areasfor one or more PLMNs supported by the radio cell; or a termination ofsupport for the radio cell by the sNB, as discussed at stage 5 of FIG.38.

In one implementation, the broadcasting the SIB in the radio cell usingthe SV for the radio cell enables each of the UEs to perform a cellchange or a handover from the radio cell to a different radio cellbefore the change of the radio cell and to access a serving PLMN via oneof the SVs using the different radio cell, e.g., as discussed at stages7-9 of FIG. 38.

In one implementation, the SIB may be a SIB type 1 (SIB1) or a SIB type2 (SIB2).

FIG. 55 shows a flowchart of an example procedure 5500 performed by asatellite Node B (e.g. an sNB 106, sNB 202 or sNB-CU 307) to assistwireless access by user equipments (e.g. including UE in FIGS. 1-3) toserving Public Land Mobile Networks (PLMNs) via space vehicles (e.g. SVs102, 202 and/or 302).

At block 5502, a plurality of tracking areas (TAs) currently supportedby a radio cell controlled by the sNB is determined, where the pluralityof TAs belong to a plurality of PLMNs supported by the radio cell, e.g.,as discussed at stage 4 of FIG. 38. A means for determining a pluralityof tracking areas (TAs) currently supported by a radio cell controlledby the sNB, wherein the plurality of TAs belong to a plurality of PLMNssupported by the radio cell may include the external interface 4106 andone or more processors 4104 with dedicated hardware or implementingexecutable code or software instructions 4120 in in memory 4116 and/ormedium 4118, such as the determine supported TAs module 4242 in sNB 4100shown in FIGS. 41 and 42.

At block 5504, a remaining lifetime for each TA in the plurality of TAsis determined, where the remaining lifetime for each TA is an amount oftime until the radio cell ceases support for that TA, e.g. as discussedat stage 5 of FIG. 38. A means for determining a remaining lifetime foreach TA in the plurality of TAs, wherein the remaining lifetime for eachTA is an amount of time until the radio cell ceases support for that TAmay include the external interface 4106 and one or more processors 4104with dedicated hardware or implementing executable code or softwareinstructions 4120 in in memory 4116 and/or medium 4118, such as thelifetime module 4240 in sNB 4100 shown in FIGS. 41 and 42.

At block 5506, a system information block (SIB) is generated indicatingeach of the plurality of TAs and the remaining lifetime for each TA inthe plurality of TAs, e.g. as discussed at stage 6 of FIG. 38. A meansfor generating a system information block (SIB) indicating each of theplurality of TAs and the remaining lifetime for each TA in the pluralityof TAs may include the one or more processors 4104 with dedicatedhardware or implementing executable code or software instructions 4120in in memory 4116 and/or medium 4118, such as the SIB module 4244 in sNB4100 shown in FIGS. 41 and 42.

At block 5508, the SIB may be broadcast in the radio cell using an SVfor the radio cell (e.g. an SV 102, 202 or 302), as discussed at stage 6of FIG. 38. A means for broadcasting the SIB in the radio cell using anSV for the radio cell may include the external interface 4106 and one ormore processors 4104 with dedicated hardware or implementing executablecode or software instructions 4120 in in memory 4116 and/or medium 4118,such as the provide lifetime/TA module 4246 in sNB 4100 shown in FIGS.41 and 42.

In one implementation, the SV may be used in a transparent mode, aregenerative mode with a non-split architecture or in a regenerativemode with a split architecture, e.g. as discussed in FIGS. 1-3. The sNBmay be terrestrial (e.g. may be an sNB 106) when the SV is used in thetransparent mode. The sNB may be part of the SV (e.g. may be an sNB 202)when the SV is used in the regenerative mode with the non-splitarchitecture. The sNB may be terrestrial and may comprise an sNB CentralUnit (e.g. an sNB-CU 307) when the SV is used in the regenerative modewith the split architecture.

In one implementation, the plurality of TAs currently supported by theradio cell may be determined by determining TAs with geographic areasoverlapping with a coverage area of the radio cell, where the overlapbetween the geographic area of each TA of the TAs and the coverage areaof the radio cell satisfies one or more criteria for each TA of the TAs,e.g., as discussed at stages 4 and 5 of FIG. 38. A means for determiningTAs with geographic areas overlapping with a coverage area of the radiocell, where the overlap between the geographic area of each TA of theTAs and the coverage area of the radio cell satisfies one or morecriteria for each TA of the TAs may include the external interface 4106and one or more processors 4104 with dedicated hardware or implementingexecutable code or software instructions 4120 in in memory 4116 and/ormedium 4118, such as the determine supported TAs module 4242 in sNB 4100shown in FIGS. 41 and 42. For example, the one or more criteria for eachTA may include inclusion of the geographic area of the each TA withinthe coverage area of the radio cell; inclusion of the coverage area ofthe radio cell within the geographic area of the each TA; an overlap ofthe coverage area of the radio cell with the geographic area of the eachTA which exceeds a threshold for the each TA; or some combination ofthese, e.g., as discussed at stages 4 and 5 of FIG. 38.

In one aspect, the first radio cell may cease support for a TA in theplurality of TAs when the overlap between the geographic area of that TAand the coverage area of the radio cell no longer satisfies the one ormore criteria for that TA.

In one implementation, the SIB may be a SIB type 1 (SIB1) or a SIB type2 (SIB2), as discussed at stage 6 of FIG. 38.

FIG. 56 shows a flowchart of an example procedure 5600 performed by auser equipment (e.g. the UE 105 in FIGS. 1-3) to assist wireless accessby the UE to a serving Public Land Mobile Network (PLMN) via spacevehicles (e.g. SVs 102, 202 and/or 302).

At block 5602, the serving PLMN is accessed via a first radio cell for afirst SV (e.g. an SV 102, 202 or 302), e.g., as discussed at stage 3 ofFIG. 38. A means for accessing the serving PLMN via a first radio cellfor a first SV may include the satellite transceiver 3903 and one ormore processors 3904 with dedicated hardware or implementing executablecode or software instructions 3920 in in memory 3916 and/or medium 3918,such as the access PLMN module 4030 in UE 3900 shown in FIGS. 39 and 40.

At block 5604, a remaining lifetime for the first radio cell broadcastby the first SV is received in a System Information Block (SIB) in thefirst radio cell, where the remaining lifetime is an amount of timeuntil a change of the first radio cell, e.g. as discussed at stage 6 ofFIG. 38. A means for accessing the serving PLMN via a first radio cellfor a first SV may include the satellite transceiver 3903 and one ormore processors 3904 with dedicated hardware or implementing executablecode or software instructions 3920 in in memory 3916 and/or medium 3918,such as the lifetime module 4032 in UE 3900 shown in FIGS. 39 and 40.

At block 5606, a handover or a cell change is performed, before thechange of the first radio cell, to a second radio cell for a second SV(e.g. an SV 102, 202 or 302), based on the remaining lifetime, where thesecond radio cell is different to the first radio cell, as discussed atstages 7 and 8 of FIG. 38. A means for accessing the serving PLMN via afirst radio cell for a first SV may include the satellite transceiver3903 and one or more processors 3904 with dedicated hardware orimplementing executable code or software instructions 3920 in in memory3916 and/or medium 3918, such as the cell change module 4034 or handovermodule 4036 in UE 3900 shown in FIGS. 39 and 40.

At block 5608, the serving PLMN is accessed using the second radio celland the second SV after the handover or the cell change, e.g. asdiscussed at stage 9 of FIG. 38. A means for accessing the serving PLMNvia a first radio cell for a first SV may include the satellitetransceiver 3903 and one or more processors 3904 with dedicated hardwareor implementing executable code or software instructions 3920 in inmemory 3916 and/or medium 3918, such as the cell change module 4034 orhandover module 4036 in UE 3900 shown in FIGS. 39 and 40.

In one implementation, the change of the first radio cell may compriseat least one of: a change of an earth station (e.g. an ES 104) used toexchange signaling for the first radio cell between the first SV andeither a satellite NodeB for the first radio cell (e.g. an sNB 106 orsNB-CU 307 when the first SV is an SV 102 or SV 302) or a core networkfor the first radio cell (e.g. a 5GCN 110 when the first SV is an SV202); a change in timing for the first radio cell; a change in carrierfrequency for the first radio cell; a change in bandwidth for the firstradio cell; a change in coverage area for the first radio cell; a changeto radio beams used by the first radio cell; a change in a cell identityfor the first radio cell; a cessation of support by the first radio cellfor one or more tracking areas for one or more PLMNs supported by thefirst radio cell; or a termination of support for the first radio cellby the sNB for the first radio cell, e.g. as discussed at stage 5 ofFIG. 38.

In one implementation, the UE performs the cell change when the UE is anidle state and performs the handover when the UE is in a connectedstate, e.g., as discussed at stage 8 of FIG. 38. When the UE is in theidle state, for example, the UE may select the second radio cell priorto the cell change based in part on a remaining lifetime for the secondradio cell, which is greater than the remaining lifetime for the firstradio cell, as discussed at stages 8 and 8 a of FIG. 38. A means forselecting the second radio cell prior to the cell change based in parton a remaining lifetime for the second radio cell which is greater thanthe remaining lifetime for the first radio cell may include thesatellite transceiver 3903 and one or more processors 3904 withdedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as the cellchange module 4034 in UE 3900 shown in FIGS. 39 and 40. When the UE isin the connected state, for example, the UE may obtain signalmeasurements for the second radio cell prior to the handover, asdiscussed at stages 8 and 8 a of FIG. 38. The UE may send the signalmeasurements to a satellite NodeB (e.g. an sNB 106, sNB 202 or sNB-CU307) for the first radio cell, where the sNB instigates the handoverbased in part on the signal measurements and a remaining lifetime forthe second radio cell which is greater than the remaining lifetime forthe first radio cell, as discussed at stages 8, 8 a, 8 b, 8 c, and 8 dof FIG. 38. A means for obtaining signal measurements for the secondradio cell prior to the handover and a means for sending the signalmeasurements to a satellite NodeB (sNB) for the first radio cell,wherein the sNB instigates the handover based in part on the signalmeasurements and a remaining lifetime for the second radio cell which isgreater than the remaining lifetime for the first radio cell may includethe satellite transceiver 3903 and one or more processors 3904 withdedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as thehandover module 4036 in UE 3900 shown in FIGS. 39 and 40.

In one implementation, the SIB may be a SIB type 1 (SIB1) or a SIB type2 (SIB2), as discussed at stage 6 of FIG. 38.

FIG. 57 shows a flowchart of an example procedure 5700 performed by auser equipment (e.g. the UE 105 in FIGS. 1-3) to assist wireless accessby the UE to a serving Public Land Mobile Network (PLMN) via spacevehicles (e.g. SVs 102, 202 and/or 302).

At block 5702, a first indication of an allowed tracking area (TA) forthe serving PLMN is received from the serving PLMN, where the UE isallowed to access the serving PLMN based on the allowed TA, e.g., asdiscussed at stage 1 of FIG. 38. A means for receiving a firstindication of an allowed tracking area (TA) for the serving PLMN fromthe serving PLMN, wherein the UE is allowed to access the serving PLMNbased on the allowed TA may include the satellite transceiver 3903 andone or more processors 3904 with dedicated hardware or implementingexecutable code or software instructions 3920 in in memory 3916 and/ormedium 3918, such as the allowed TAs module 4038 in UE 3900 shown inFIGS. 39 and 40.

At block 5704, a second indication is received in a first radio cell fora first SV (e.g. an SV 102, 202 or 302), where the first radio cell isavailable to the UE, and where the second indication indicates supportby the first radio cell for the serving PLMN and the allowed TA, e.g.,as discussed at stage 2 of FIG. 38. A means for receiving a secondindication in a first radio cell for a first SV, wherein the first radiocell is available to the UE, and wherein the second indication indicatessupport by the first radio cell for the serving PLMN and the allowed TAinclude the satellite transceiver 3903 and one or more processors 3904with dedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as the PLMNsupport module 4040 in UE 3900 shown in FIGS. 39 and 40.

At block 5706, the serving PLMN is accessed based on the allowed TA viathe first SV and the first radio cell, as discussed at stage 3 of FIG.38. A means for accessing the serving PLMN based on the allowed TA viathe first SV and the first radio cell may include the satellitetransceiver 3903 and one or more processors 3904 with dedicated hardwareor implementing executable code or software instructions 3920 in inmemory 3916 and/or medium 3918, such as the access PLMN module 4030 inUE 3900 shown in FIGS. 39 and 40.

At block 5708, a remaining lifetime for the allowed TA in the firstradio cell is received, where the remaining lifetime is broadcast by thefirst SV in a System Information Block (SIB) for the first radio cell,and where the remaining lifetime is an amount of time until the firstradio cell ceases support for the allowed TA, e.g. as discussed atstages 5 and 6 of FIG. 38. A means for receiving a remaining lifetimefor the allowed TA in the first radio cell, wherein the remaininglifetime is broadcast by the first SV in a System Information Block(SIB) for the first radio cell, and wherein the remaining lifetime is anamount of time until the first radio cell ceases support for the allowedTA may include the satellite transceiver 3903 and one or more processors3904 with dedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as thelifetime module 4032 in UE 3900 shown in FIGS. 39 and 40.

At block 5710, a handover or a cell change to a second radio cell for asecond SV (e.g. an SV 102, 202 or 302) is performed before the firstradio cell ceases support for the allowed TA, based on the remaininglifetime of the allowed TA in the first radio cell, where the secondradio cell is different to the first radio cell, and where the secondradio cell indicates support for the serving PLMN and the allowed TA,e.g. as discussed for stages 7 and 8 of FIG. 38. A means for performinga handover or a cell change to a second radio cell for a second SV,before the first radio cell ceases support for the allowed TA, based onthe remaining lifetime of the allowed TA in the first radio cell,wherein the second radio cell is different to the first radio cell, andwherein the second radio cell indicates support for the serving PLMN andthe allowed TA may include the satellite transceiver 3903 and one ormore processors 3904 with dedicated hardware or implementing executablecode or software instructions 3920 in in memory 3916 and/or medium 3918,such as the cell change module 4034 or handover module 4036 in UE 3900shown in FIGS. 39 and 40.

At block 5712, the serving PLMN may be accessed based on the allowed TAvia the second SV and the second radio cell after the handover or thecell change, e.g. as discussed at stage 9 of FIG. 38. A means foraccessing the serving PLMN based on the allowed TA via the second SV andthe second radio cell after the handover or the cell change may includethe satellite transceiver 3903 and one or more processors 3904 withdedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as theaccess PLMN module 4030 in UE 3900 shown in FIGS. 39 and 40.

In one implementation, the UE may perform the cell change when the UE isin an idle state and the UE may perform the handover when the UE is in aconnected state, e.g. as discussed at stage 8 of FIG. 38. When the UE isin the idle state, for example, the UE may select the second radio cellprior to the cell change based in part on a remaining lifetime for theallowed TA in the second radio cell which is greater than the remaininglifetime for the allowed TA in the first radio cell, e.g. as discussedat stages 8 and 8 a of FIG. 38. A means for selecting the second radiocell prior to the cell change based in part on a remaining lifetime forthe allowed TA in the second radio cell which is greater than theremaining lifetime for the allowed TA in the first radio cell mayinclude the satellite transceiver 3903 and one or more processors 3904with dedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as the cellchange module 4034 in UE 3900 shown in FIGS. 39 and 40. When the UE isin the connected state, the UE may obtain signal measurements for thesecond radio cell prior to the handover as discussed at stages 8 and 8 aof FIG. 38. The UE may then send the signal measurements to a satelliteNodeB (e.g. an sNB 106, sNB 202 or sNB-CU 307) for the first radio cell,where the sNB instigates the handover based in part on the signalmeasurements and a remaining lifetime for the allowed TA in the secondradio cell which is greater than the remaining lifetime for the allowedTA in the first radio cell, e.g. as discussed at stages 8, 8 a, 8 b, 8c, and 8 d of FIG. 38. A means for obtaining signal measurements for thesecond radio cell prior to the handover and a means for sending thesignal measurements to a satellite NodeB (sNB) for the first radio cell,wherein the sNB instigates the handover based in part on the signalmeasurements and a remaining lifetime for the allowed TA in the secondradio cell which is greater than the remaining lifetime for the allowedTA in the first radio cell may include the satellite transceiver 3903and one or more processors 3904 with dedicated hardware or implementingexecutable code or software instructions 3920 in in memory 3916 and/ormedium 3918, such as the handover module 4036 in UE 3900 shown in FIGS.39 and 40.

In one implementation, the UE may access the serving PLMN based on theallowed TA via an SV (e.g. an SV 102, 202 or 302) and a radio cell forthe SV by: determining whether the UE is located inside the allowed TA;determining whether the radio cell supports the serving PLMN and theallowed TA; and accessing the serving PLMN via the SV and the radio cellfor the SV when the UE determines the UE is located inside the allowedTA and the UE determines the radio cell supports the serving PLMN andthe allowed TA, e.g., as discussed at stage 3 and 9 of FIG. 38. The SVmay be the first SV, the second SV or another SV. A means fordetermining whether the UE is located inside the allowed TA may includethe satellite transceiver 3903 and one or more processors 3904 withdedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as thelocation in TA module 4042 in UE 3900 shown in FIGS. 39 and 40. A meansfor determining whether the radio cell supports the serving PLMN and theallowed TA may include the satellite transceiver 3903 and one or moreprocessors 3904 with dedicated hardware or implementing executable codeor software instructions 3920 in in memory 3916 and/or medium 3918, suchas the access PLMN module 4030 in UE 3900 shown in FIGS. 39 and 40. Ameans for accessing the serving PLMN via the first SV and the firstradio cell for the first SV when the UE determines the UE is locatedinside the allowed TA and the UE determines the radio cell supports theserving PLMN and the allowed TA may include the satellite transceiver3903 and one or more processors 3904 with dedicated hardware orimplementing executable code or software instructions 3920 in in memory3916 and/or medium 3918, such as the access PLMN module 4030 in UE 3900shown in FIGS. 39 and 40.

In one implementation, the UE may access the serving PLMN based on theallowed TA via an SV (e.g. an SV 102, 202 or 302) and a radio cell forthe SV by: determining whether the radio cell supports the serving PLMNand the allowed TA; receiving a third indication (e.g. a Registrationflag) that the UE may access the serving PLMN via the SV and the radiocell for the SV when the UE is not located in the allowed TA; andaccessing the serving PLMN via the SV and the radio cell for the SV whenthe UE determines the serving PLMN and the allowed TA are supported bythe radio cell and, e.g., as discussed at stages 8 and 9 of FIG. 38. TheUE may then either be located inside the allowed TA or not locatedinside the allowed TA. The SV may be the first SV, the second SV oranother SV. The third indication, for example, may be received from theserving PLMN along with the first indication, e.g., providing theallowed tracking area (TA) for the serving PLMN, e.g., as discussed atstages 1 and 9 of FIG. 38. A means for determining whether the radiocell supports the serving PLMN and the allowed TA may include thesatellite transceiver 3903 and one or more processors 3904 withdedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as theaccess PLMN module 4030 in UE 3900 shown in FIGS. 39 and 40. A means forreceiving a third indication that the UE may access the serving PLMN viathe SV and the radio cell for the SV when the UE is not located in theallowed TA may include the satellite transceiver 3903 and one or moreprocessors 3904 with dedicated hardware or implementing executable codeor software instructions 3920 in in memory 3916 and/or medium 3918, suchas the access PLMN module 4030 in UE 3900 shown in FIGS. 39 and 40. Ameans for accessing the serving PLMN via the first SV and the firstradio cell for the first SV when the UE determines the serving PLMN andthe allowed TA are supported by the radio cell and when the UE is eitherlocated inside the allowed TA or not located inside the allowed TA mayinclude the satellite transceiver 3903 and one or more processors 3904with dedicated hardware or implementing executable code or softwareinstructions 3920 in in memory 3916 and/or medium 3918, such as theaccess PLMN module 4030 or access when not in TA module 4044 in UE 3900shown in FIGS. 39 and 40.

In one implementation, the SIB may be a SIB type 1 (SIB1) or SIB type 2(SIB2), as discussed at stage 6 of FIG. 38.

In one implementation, the UE may receive the first indication in aNon-Access Stratum (NAS) Registration Accept message sent by an Accessand Mobility management Function (e.g. an AMF 122) in the serving PLMN,e.g. as discussed at stage 1 of FIG. 38.

Abbreviations used herein may be identified in Table 2 as follows:

TABLE 2 EM Emergency ES Earth Station GEO Geostationary Earth Orbit ISLInter-Satellite Links LEO Low Earth Orbit LI Lawful Interception MEOMedium Earth Orbit MNO Mobile Network Operator NGEO Non-GeostationaryEarth Orbiting NTN Non-Terrestrial Network sNB satellite Node B SV SpaceVehicle SVO SV Operator TA Tracking Area TAC Tracking Area Code TAITracking Area Identity WEA Wireless Emergency Alerting

Substantial variations may be made in accordance with specific desires.For example, customized hardware might also be used, and/or particularelements might be implemented in hardware, software (including portablesoftware, such as applets, etc.), or both. Further, connection to othercomputing devices such as network input/output devices may be employed.

Configurations may be described as a process which is depicted as a flowdiagram or block diagram. Although each may describe the operations as asequential process, many of the operations may be performed in parallelor concurrently. In addition, the order of the operations may berearranged. A process may have additional steps not included in thefigure. Furthermore, examples of the methods may be implemented byhardware, software, firmware, middleware, microcode, hardwaredescription languages, or any combination thereof. When implemented insoftware, firmware, middleware, or microcode, the program code or codesegments to perform the necessary tasks may be stored in anon-transitory computer-readable medium such as a storage medium.Processors may perform the described tasks.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly or conventionally understood. As usedherein, the articles “a” and “an” refer to one or to more than one(i.e., to at least one) of the grammatical object of the article. By wayof example, “an element” means one element or more than one element.“About” and/or “approximately” as used herein when referring to ameasurable value such as an amount, a temporal duration, and the like,encompasses variations of ±20% or ±10%, ±5%, or +0.1% from the specifiedvalue, as such variations are appropriate in the context of the systems,devices, circuits, methods, and other implementations described herein.“Substantially” as used herein when referring to a measurable value suchas an amount, a temporal duration, a physical attribute (such asfrequency), and the like, also encompasses variations of ±20% or ±10%,±5%, or +0.1% from the specified value, as such variations areappropriate in the context of the systems, devices, circuits, methods,and other implementations described herein.

As used herein, including in the claims, “or” as used in a list of itemsprefaced by “at least one of” or “one or more of” indicates adisjunctive list such that, for example, a list of “at least one of A,B, or C” means A or B or C or AB or AC or BC or ABC (i.e., A and B andC), or combinations with more than one feature (e.g., AA, AAB, ABBC,etc.). Also, as used herein, unless otherwise stated, a statement that afunction or operation is “based on” an item or condition means that thefunction or operation is based on the stated item or condition and maybe based on one or more items and/or conditions in addition to thestated item or condition.

As used herein, a mobile device, user equipment (UE), or mobile station(MS) refers to a device such as a cellular or other wirelesscommunication device, a smartphone, tablet, personal communicationsystem (PCS) device, personal navigation device (PND), PersonalInformation Manager (PIM), Personal Digital Assistant (PDA), laptop orother suitable mobile device which is capable of receiving wirelesscommunication and/or navigation signals, such as navigation positioningsignals. The term “mobile station” (or “mobile device”. “wirelessdevice” or “user equipment”) is also intended to include devices whichcommunicate with a personal navigation device (PND), such as byshort-range wireless, infrared, wireline connection, or otherconnection—regardless of whether satellite signal reception, assistancedata reception, and/or position-related processing occurs at the deviceor at the PND. Also, a “mobile station” or “user equipment” is intendedto include all devices, including wireless communication devices,computers, laptops, tablet devices, etc., which are capable ofcommunication with a server, such as via the Internet, WiFi, or othernetwork, and to communicate with one or more types of nodes, regardlessof whether satellite signal reception, assistance data reception, and/orposition-related processing occurs at the device, at a server, or atanother device or node associated with the network. Any operablecombination of the above are also considered a “mobile station” or “userequipment.” A mobile device or user equipment (UE) may also be referredto as a mobile terminal, a terminal, a device, a Secure User PlaneLocation Enabled Terminal (SET), a target device, a target, or by someother name.

In an embodiment, a first example independent claim may include a methodfor supporting location of a user equipment (UE) at a first wirelessnode, comprising receiving a first request for broadcast of an increasedquantity of location-related information, the broadcast based on awireless access type for the first wireless node; and broadcasting theincreased quantity of location-related information using the wirelessaccess type and based on the first request.

Example dependent claims may include one or more of the followingfeatures. The wireless access type is Fifth Generation (5G), New Radio(NR) or Long Term Evolution (LTE). The location-related informationcomprises a Positioning Reference Signal (PRS). The increased quantityof location-related information comprises an increased PRS bandwidth, anincreased frequency of PRS positioning occasions, an increased durationfor a PRS positioning occasion, an increased number of separate PRSsignals, a transmission of PRS using an uplink carrier frequency, orsome combination thereof. The method may further include sending asecond request for a muting of transmission to a second wireless nodefor the wireless access type, wherein the muting of transmission isbased on avoiding radio interference with the broadcast of the increasedquantity of location-related information by the first wireless node. Thelocation-related information may comprise location assistance data. Thelocation assistance data may comprise assistance data for Observed TimeDifference Of Arrival (OTDOA), assistance data for Assisted GlobalNavigation Satellite System (A-GNSS), assistance data for Real TimeKinematics (RTK), assistance data for Precise Point Positioning (PPP),assistance data for Differential GNSS (DGNSS), or any combinationthereof. The increased quantity of location-related information maycomprise an increased quantity of location assistance data, additionaltypes of location assistance data, an increased frequency ofbroadcasting location assistance data, an increased repetition of thebroadcasting of the location assistance data, or any combinationthereof. The first request may be received from a third wireless node.The first request may be received from the UE. The first request may bereceived using a Radio Resource Control (RRC) protocol for the wirelessaccess type. The first wireless node may be a serving wireless node forthe UE based on the wireless access type. The method may further includesending a third request for the broadcast of an increased quantity oflocation-related information to a fourth wireless node for the wirelessaccess type, wherein the third request is based on the first request.The method may further include sending a response to the UE, wherein theresponse comprises a confirmation of the broadcasting of the increasedquantity of location-related information by the first wireless node. Themethod may further include receiving a fourth request from the UE for atermination of the broadcast of the increased quantity oflocation-related information, and terminating the broadcasting of theincreased quantity of location-related information using the wirelessaccess type based on the fourth request.

While some of the techniques, processes, and/or implementationspresented herein may comply with all or part of one or more standards,such techniques, processes, and/or implementations may not, in someembodiments, comply with part or all of such one or more standards.

Implementation examples are described in the following numbered clauses:

1. A method performed by a first network node for transferring signalingfor a first plurality of radio cells from a first earth station to asecond earth station, wherein the first plurality of radio cells issupported by a space vehicle (SV), the method comprising:

transporting first signaling between a first plurality of UserEquipments (UEs) and a Core Network at a first time, wherein the firstsignaling is transported via the SV, the first earth station and thefirst network node, and wherein the first signaling is transportedbetween the SV and the first plurality of UEs using the first pluralityof radio cells;

ceasing to transport the first signaling between the first plurality ofUEs and the Core Network at a second time, wherein the second time issubsequent to the first time; and

enabling the transport of second signaling between the first pluralityof UEs and the Core Network after the second time via the SV, the secondearth station and a second network node, wherein the second signaling istransported between the SV and the first plurality of UEs using thefirst plurality of radio cells.

2. The method of clause 1, wherein the first signaling and the secondsignaling comprise user plane signaling and control plane signaling,wherein the user plane signaling includes signaling for data and voiceconnections between each of the plurality of UEs and external entities,and wherein the control plane signaling includes signaling forconnections and associations between each of the plurality of UEs andentities in the Core Network.

3. The method of either of clause 1 or 2, wherein each radio cell in thefirst plurality of radio cells comprises one or more radio beamssupported by the SV.

4. The method of any of clauses 1-3, wherein the first network node andthe second network node comprise a same satellite NodeB (sNB), whereinthe first signaling and the second signaling are transported via the SVin a transparent mode, wherein enabling the transport of the secondsignaling between the plurality of UEs and the Core Network after thesecond time comprises at least one of:

determining a timing for each radio cell in the first plurality of radiocells, wherein the timing is applicable after the second time, andproviding the timing of a serving radio cell in the first plurality ofradio cells to each UE in the first plurality of UEs before the secondtime;

determining a timing advance for each UE in the first plurality of UEs,wherein the timing advance is applicable after the second time, andproviding the timing advance to each UE in the first plurality of UEsbefore the second time; or

a combination thereof.

5. The method of clause 4, wherein determining the timing for each radiocell in the first plurality of radio cells is based on (i) a knownorbital position of the SV, and (ii) known or measured propagation andtransmission delays for: signaling links between the sNB and the firstearth station, signaling links between the first earth station and theSV; signaling links between the sNB and the second earth station;signaling links between the second earth station and the SV; andsignaling links between the SV and the first plurality of UEs.

6. The method of any of clauses 1-3, wherein the first network node andthe second network node comprise a same satellite Node B (sNB), whereinthe sNB is included within the SV, and wherein the first signaling andthe second signaling are transported via the SV in a regenerative mode.

7. The method of clause 6, wherein the first earth station and thesecond earth station act as Level 1 relays, wherein enabling thetransport of the second signaling between the plurality of UEs and theCore Network after the second time comprises:

transferring, at the second time, a plurality of data links from thefirst earth station to the second earth station, wherein each data linkin the plurality of data links comprises a Level 2 connection betweenthe sNB and the core network, and wherein signaling for each data linkin the plurality of data links is transported through the first earthstation at a Level 1 prior to the second time and is transported throughthe second earth station at a Level 1 after the second time.

8. The method of clause 6, wherein the first earth station and thesecond earth station act as Level 2 relays, wherein enabling thetransport of the second signaling between the plurality of UEs and theCore Network after the second time comprises:

-   -   releasing, immediately prior to the second time, a first        plurality of data links between the sNB and the core network,        wherein the first plurality of data links transports the first        signaling, and wherein each data link in the first plurality of        data links comprises a Level 2 connection between the sNB and        the first earth station and a concatenated Level 2 connection        between the first earth station and the core network;    -   transferring, at the second time and from the first earth        station to the second earth station, a Level 1 transport of        signaling between the sNB and the core network; and

establishing, immediately after the second time, a second plurality ofdata links between the sNB and the core network, wherein the secondplurality of data links transports the second signaling, wherein eachdata link in the second plurality of data links comprises a Level 2connection between the sNB and the second earth station and aconcatenated Level 2 connection between the second earth station and thecore network, and wherein each data link in the second plurality of datalinks corresponds to one data link in the first plurality of data links.

9. The method of any of clauses 1-3, wherein the SV is used in aregenerative mode with a split architecture, wherein the SV includes asatellite NodeB (sNB) Distributed Unit (sNB-DU), wherein the sNB-DUcommunicates with a first sNB Central Unit (sNB-CU) to transport thefirst signaling and with a second sNB-CU to transport the secondsignaling, wherein the first signaling is transported between the sNB-DUand the core network via the first sNB-CU, and wherein the secondsignaling is transported between the sNB-DU and the core network via thesecond sNB-CU.

10. The method of clause 9, wherein the first sNB-CU comprises thesecond sNB-CU, the first network node comprises the second network node,and wherein the first network node comprises the sNB-DU or the firstsNB-CU.

11. The method of clause 10, wherein the first earth station and thesecond earth station act as Level 1 relays, wherein enabling thetransport of the second signaling between the plurality of UEs and theCore Network after the second time comprises:

-   -   transferring, at the second time, a plurality of data links from        the first earth station to the second earth station, wherein        each data link in the plurality of data links comprises a Level        2 connection between the first network node and the other of the        sNB-DU and the first sNB-CU, wherein each data link in the        plurality of data links is transported through the first earth        station at a Level 1 prior to the second time and is transported        through the second earth station at a Level 1 after the second        time.

12. The method of clause 10, wherein the first earth station and thesecond earth station act as a Level 2 relays, wherein enabling thetransport of the second signaling between the first plurality of UEs andthe Core Network after the second time comprises:

-   -   releasing, immediately prior to the second time, a first        plurality of data links between the first network node and the        other of the sNB-DU and the first sNB-CU, wherein the first        plurality of data links transports the first signaling, and        wherein each data link in the first plurality of data links        comprises a Level 2 connection between the first network node        and the first earth station and a concatenated Level 2        connection between the first earth station and the other of the        sNB-DU and the first sNB-CU;    -   transferring, at the second time and from the first earth        station to the second earth station, a Level 1 transport of        signaling between the first network node and the other of the        sNB-DU and the first sNB-CU; and

establishing, immediately after the second time, a second plurality ofdata links between the first network node and the other of the sNB-DUand the first sNB-CU, wherein the second plurality of data linkstransports the second signaling, wherein each data link in the secondplurality of data links comprises a Level 2 connection between the firstnetwork node and the second earth station and a concatenated Level 2connection between the second earth station and the other of the sNB-DUand the first sNB-CU, and wherein each data link in the second pluralityof data links corresponds to one data link in the first plurality ofdata links.

13. The method of clause 9, wherein the first sNB-CU is different thanthe second sNB-CU, and further comprising:

-   -   enabling the transport of the second signaling between the first        plurality of UEs and the Core Network after the second time via        the SV by performing a modified handover procedure for each UE        in the first plurality of UEs, wherein either (i) the first        network node comprises the first sNB-CU and the second network        node comprises the second sNB-CU, or (ii) the first network node        and the second network node each comprise the sNB-DU.

14. The method of clause 13, wherein performing the modified handoverprocedure for each UE in the first plurality of UEs comprises at leastone of:

-   -   releasing first non-UE associated links and connections between        the sNB-DU and the first sNB-CU immediately before the second        time, wherein signaling for the first non-UE associated links        and connections is transported between the sNB-DU and the first        sNB-CU via the first earth station at a Level 1 or a Level 2;    -   establishing second non-UE associated links and connections        between the sNB-DU and the second sNB-CU immediately after the        second time, wherein signaling for the second non-UE associated        links and connections is transported between the sNB-DU and the        second sNB-CU via the second earth station at a Level 1 or a        Level 2;    -   releasing first UE associated connections and tunnels between        the sNB-DU, the first sNB-CU and the core network immediately        before the second time, wherein signaling for the first UE        associated connections and tunnels is transported between the        sNB-DU and the first sNB-CU using the first non-UE associated        links and connections;    -   establishing second UE associated connections and tunnels        between the sNB-DU, the second sNB-CU and the core network        immediately after the second time, wherein signaling for the        second UE associated connections and tunnels is transported        between the sNB-DU and the second sNB-CU via the second earth        station using the second non-UE associated links and        connections; or

a combination thereof.

15. The method of clause 14, wherein the first non-UE associated linksand connections and the second non-UE associated links and connectionseach include use of one or more of an Internet Protocol (IP), a UserDatagram Protocol (UDP), and a Stream Control Transmission Protocol(SCTP).

16. The method of clause 14, wherein the first UE associated connectionsand tunnels and the second UE associated connections and tunnels eachinclude use of one or more of a GPRS Tunneling Protocol (GTP), an F1Application Protocol (F1AP), a Packet Data Convergence Protocol (PDCP),a Service Data Protocol (SDAP), a Radio Resource Control (RRC) protocol,a Next Generation Application Protocol (NGAP), an NR User Plane Protocol(NRUPP), or a combination thereof.

17. The method of any of clauses 1-16, further comprising:

transporting third signaling between a second plurality of UEs and theCore Network at the first time, wherein the third signaling istransported via the SV, the first earth station and the first networknode, wherein the third signaling is transported between the SV and thesecond plurality of UEs using a second plurality of radio cells; and

handing over the second plurality of UEs before the second time to athird plurality of radio cells supported by one or more SVs differentfrom the SV, wherein fourth signaling is transported between the secondplurality of UEs and the Core Network after the second time, and whereinthe fourth signaling is transported via the one or more SVs using thethird plurality of radio cells.

18. A first network node configured for transferring signaling for afirst plurality of radio cells from a first earth station to a secondearth station, wherein the first plurality of radio cells is supportedby a space vehicle (SV), the first network node comprising:

an external interface configured to communicate with network nodes;

at least one memory;

at least one processor coupled to the external interface and the atleast one memory, wherein the at least one processor is configured to:

transport, via the external interface, first signaling between a firstplurality of User Equipments (UEs) and a Core Network at a first time,wherein the first signaling is transported via the SV, the first earthstation and the first network node, and wherein the first signaling istransported between the SV and the first plurality of UEs using thefirst plurality of radio cells;

cease to transport the first signaling between the first plurality ofUEs and the Core Network at a second time, wherein the second time issubsequent to the first time; and

enable the transport of second signaling between the first plurality ofUEs and the Core Network after the second time via the SV, the secondearth station and a second network node, wherein the second signaling istransported between the SV and the first plurality of UEs using thefirst plurality of radio cells.

19. The first network node of clause 18, wherein the first signaling andthe second signaling comprise user plane signaling and control planesignaling, wherein the user plane signaling includes signaling for dataand voice connections between each of the plurality of UEs and externalentities, and wherein the control plane signaling includes signaling forconnections and associations between each of the plurality of UEs andentities in the Core Network.

20. The first network node of either of clauses 18 or 19, wherein eachradio cell in the first plurality of radio cells comprises one or moreradio beams supported by the SV.

21. The first network node of any of clauses 18-20, wherein the firstnetwork node and the second network node comprise a same satellite NodeB(sNB), wherein the first signaling and the second signaling aretransported via the SV in a transparent mode, wherein the at least oneprocessor is configured to enable the transport of the second signalingbetween the plurality of UEs and the Core Network after the second timeby being configured to at least one of:

determine a timing for each radio cell in the first plurality of radiocells, wherein the timing is applicable after the second time, andprovide the timing of a serving radio cell in the first plurality ofradio cells to each UE in the first plurality of UEs before the secondtime;

determine a timing advance for each UE in the first plurality of UEs,wherein the timing advance is applicable after the second time, andprovide the timing advance to each UE in the first plurality of UEsbefore the second time; or

a combination thereof.

22. The first network node of clause 21, wherein the at least oneprocessor is configured to determine the timing for each radio cell inthe first plurality of radio cells based on (i) a known orbital positionof the SV, and (ii) known or measured propagation and transmissiondelays for: signaling links between the sNB and the first earth station,signaling links between the first earth station and the SV; signalinglinks between the sNB and the second earth station; signaling linksbetween the second earth station and the SV; and signaling links betweenthe SV and the first plurality of UEs.

23. The first network node of any of clauses 18-20, wherein the firstnetwork node and the second network node comprise a same satellite NodeB (sNB), wherein the sNB is included within the SV, and wherein thefirst signaling and the second signaling are transported via the SV in aregenerative mode.

24. The first network node of clause 23, wherein the first earth stationand the second earth station act as Level 1 relays, wherein the at leastone processor is configured to enable the transport of the secondsignaling between the plurality of UEs and the Core Network after thesecond time by being configured to:

transfer, at the second time, a plurality of data links from the firstearth station to the second earth station, wherein each data link in theplurality of data links comprises a Level 2 connection between the sNBand the core network, and wherein signaling for each data link in theplurality of data links is transported through the first earth stationat a Level 1 prior to the second time and is transported through thesecond earth station at a Level 1 after the second time.

25. The first network node of clause 23, wherein the first earth stationand the second earth station act as Level 2 relays, wherein the at leastone processor is configured to enable the transport of the secondsignaling between the plurality of UEs and the Core Network after thesecond time by being configured to:

-   -   release, immediately prior to the second time, a first plurality        of data links between the sNB and the core network, wherein the        first plurality of data links transports the first signaling,        and wherein each data link in the first plurality of data links        comprises a Level 2 connection between the sNB and the first        earth station and a concatenated Level 2 connection between the        first earth station and the core network;    -   transfer, at the second time and from the first earth station to        the second earth station, a Level 1 transport of signaling        between the sNB and the core network; and

establish, immediately after the second time, a second plurality of datalinks between the sNB and the core network, wherein the second pluralityof data links transports the second signaling, wherein each data link inthe second plurality of data links comprises a Level 2 connectionbetween the sNB and the second earth station and a concatenated Level 2connection between the second earth station and the core network, andwherein each data link in the second plurality of data links correspondsto one data link in the first plurality of data links.

26. The first network node of any of clauses 18-20, wherein the SV isused in a regenerative mode with a split architecture, wherein the SVincludes a satellite NodeB (sNB) Distributed Unit (sNB-DU), wherein thesNB-DU communicates with a first sNB Central Unit (sNB-CU) to transportthe first signaling and with a second sNB-CU to transport the secondsignaling, wherein the first signaling is transported between the sNB-DUand the core network via the first sNB-CU, and wherein the secondsignaling is transported between the sNB-DU and the core network via thesecond sNB-CU.

27. The first network node of clause 26, wherein the first sNB-CUcomprises the second sNB-CU, the first network node comprises the secondnetwork node, and wherein the first network node comprises the sNB-DU orthe first sNB-CU.

28. The first network node of clause 27, wherein the first earth stationand the second earth station act as Level 1 relays, wherein the at leastone processor is configured to enable the transport of the secondsignaling between the plurality of UEs and the Core Network after thesecond time by being configured to:

-   -   transfer, at the second time, a plurality of data links from the        first earth station to the second earth station, wherein each        data link in the plurality of data links comprises a Level 2        connection between the first network node and the other of the        sNB-DU and the first sNB-CU, wherein each data link in the        plurality of data links is transported through the first earth        station at a Level 1 prior to the second time and is transported        through the second earth station at a Level 1 after the second        time.

29. The first network node of clause 27, wherein the first earth stationand the second earth station act as a Level 2 relays, wherein the atleast one processor is configured to enable the transport of the secondsignaling between the first plurality of UEs and the Core Network afterthe second time by being configured to:

-   -   release, immediately prior to the second time, a first plurality        of data links between the first network node and the other of        the sNB-DU and the first sNB-CU, wherein the first plurality of        data links transports the first signaling, and wherein each data        link in the first plurality of data links comprises a Level 2        connection between the first network node and the first earth        station and a concatenated Level 2 connection between the first        earth station and the other of the sNB-DU and the first sNB-CU;    -   transfer, at the second time and from the first earth station to        the second earth station, a Level 1 transport of signaling        between the first network node and the other of the sNB-DU and        the first sNB-CU; and

establish, immediately after the second time, a second plurality of datalinks between the first network node and the other of the sNB-DU and thefirst sNB-CU, wherein the second plurality of data links transports thesecond signaling, wherein each data link in the second plurality of datalinks comprises a Level 2 connection between the first network node andthe second earth station and a concatenated Level 2 connection betweenthe second earth station and the other of the sNB-DU and the firstsNB-CU, and wherein each data link in the second plurality of data linkscorresponds to one data link in the first plurality of data links.

30. The first network node of clause 26, wherein the first sNB-CU isdifferent than the second sNB-CU, and the at least one processor isfurther configured to:

-   -   enable the transport of the second signaling between the first        plurality of UEs and the Core Network after the second time via        the SV by performing a modified handover procedure for each UE        in the first plurality of UEs, wherein either (i) the first        network node comprises the first sNB-CU and the second network        node comprises the second sNB-CU, or (ii) the first network node        and the second network node each comprise the sNB-DU.

31. The first network node of clause 30, wherein the at least oneprocessor is configured to perform the modified handover procedure foreach UE in the first plurality of UEs by being configured to at leastone of:

-   -   release first non-UE associated links and connections between        the sNB-DU and the first sNB-CU immediately before the second        time, wherein signaling for the first non-UE associated links        and connections is transported between the sNB-DU and the first        sNB-CU via the first earth station at a Level 1 or a Level 2;    -   establish second non-UE associated links and connections between        the sNB-DU and the second sNB-CU immediately after the second        time, wherein signaling for the second non-UE associated links        and connections is transported between the sNB-DU and the second        sNB-CU via the second earth station at a Level 1 or a Level 2;    -   release first UE associated connections and tunnels between the        sNB-DU, the first sNB-CU and the core network immediately before        the second time, wherein signaling for the first UE associated        connections and tunnels is transported between the sNB-DU and        the first sNB-CU using the first non-UE associated links and        connections;    -   establish second UE associated connections and tunnels between        the sNB-DU, the second sNB-CU and the core network immediately        after the second time, wherein signaling for the second UE        associated connections and tunnels is transported between the        sNB-DU and the second sNB-CU via the second earth station using        the second non-UE associated links and connections; or

a combination thereof.

32. The first network node of clause 31, wherein the first non-UEassociated links and connections and the second non-UE associated linksand connections each include use of one or more of an Internet Protocol(IP), a User Datagram Protocol (UDP), and a Stream Control TransmissionProtocol (SCTP).

33. The first network node of clause 31, wherein the first UE associatedconnections and tunnels and the second UE associated connections andtunnels each include use of one or more of a GPRS Tunneling Protocol(GTP), an F1 Application Protocol (F1AP), a Packet Data ConvergenceProtocol (PDCP), a Service Data Protocol (SDAP), a Radio ResourceControl (RRC) protocol, a Next Generation Application Protocol (NGAP) anNR User Plane Protocol (NRUPP), or a combination thereof.

34. The first network node of any of clauses 18-33, the at least oneprocessor is further configured to:

transport third signaling between a second plurality of UEs and the CoreNetwork at the first time, wherein the third signaling is transportedvia the SV, the first earth station and the first network node, whereinthe third signaling is transported between the SV and the secondplurality of UEs using a second plurality of radio cells; and

hand over the second plurality of UEs before the second time to a thirdplurality of radio cells supported by one or more SVs different from theSV, wherein fourth signaling is transported between the second pluralityof UEs and the Core Network after the second time, and wherein thefourth signaling is transported via the one or more SVs using the thirdplurality of radio cells.

35. A first network node configured for transferring signaling for afirst plurality of radio cells from a first earth station to a secondearth station, wherein the first plurality of radio cells is supportedby a space vehicle (SV), the first network node comprising:

means for transporting first signaling between a first plurality of UserEquipments (UEs) and a Core Network at a first time, and wherein thefirst signaling is transported via the SV, the first earth station andthe first network node, wherein the first signaling is transportedbetween the SV and the first plurality of UEs using the first pluralityof radio cells;

means for ceasing to transport the first signaling between the firstplurality of UEs and the Core Network at a second time, wherein thesecond time is subsequent to the first time; and

means for enabling the transport of second signaling between the firstplurality of UEs and the Core Network after the second time via the SV,the second earth station and a second network node, wherein the secondsignaling is transported between the SV and the first plurality of UEsusing the first plurality of radio cells.

36. A non-transitory storage medium including program code storedthereon, the program code is operable to configure at least oneprocessor in a first network node for transferring signaling for a firstplurality of radio cells from a first earth station to a second earthstation, wherein the first plurality of radio cells is supported by aspace vehicle (SV), comprising:

program code to transport first signaling between a first plurality ofUser Equipments (UEs) and a Core Network at a first time, and whereinthe first signaling is transported via the SV, the first earth stationand the first network node, wherein the first signaling is transportedbetween the SV and the first plurality of UEs using the first pluralityof radio cells;

program code to cease to transport the first signaling between the firstplurality of UEs and the Core Network at a second time, wherein thesecond time is subsequent to the first time; and

program code to enabling the transport of second signaling between thefirst plurality of UEs and the Core Network after the second time viathe SV, the second earth station and a second network node, wherein thesecond signaling is transported between the SV and the first pluralityof UEs using the first plurality of radio cells.

Although particular embodiments have been disclosed herein in detail,this has been done by way of example for purposes of illustration only,and is not intended to be limiting with respect to the scope of theappended claims, which follow. In particular, it is contemplated thatvarious substitutions, alterations, and modifications may be madewithout departing from the spirit and scope of the invention as definedby the claims. Other aspects, advantages, and modifications areconsidered to be within the scope of the following claims. The claimspresented are representative of the embodiments and features disclosedherein. Other unclaimed embodiments and features are also contemplated.Accordingly, other embodiments are within the scope of the followingclaims.

What is claimed is:
 1. A method performed by a first network node fortransferring signaling for a first plurality of radio cells from a firstearth station to a second earth station, wherein the first plurality ofradio cells is supported by a space vehicle (SV), the method comprising:transporting first signaling between a first plurality of UserEquipments (UEs) and a Core Network at a first time, wherein the firstsignaling is transported via the SV, the first earth station and thefirst network node, and wherein the first signaling is transportedbetween the SV and the first plurality of UEs using the first pluralityof radio cells; ceasing to transport the first signaling between thefirst plurality of UEs and the Core Network at a second time, whereinthe second time is subsequent to the first time; and enabling thetransport of second signaling between the first plurality of UEs and theCore Network after the second time via the SV, the second earth stationand a second network node, wherein the second signaling is transportedbetween the SV and the first plurality of UEs using the first pluralityof radio cells.
 2. The method of claim 1, wherein the first signalingand the second signaling comprise user plane signaling and control planesignaling, wherein the user plane signaling includes signaling for dataand voice connections between each of the plurality of UEs and externalentities, and wherein the control plane signaling includes signaling forconnections and associations between each of the plurality of UEs andentities in the Core Network.
 3. The method of claim 1, wherein thefirst network node and the second network node comprise a same satelliteNodeB (sNB), wherein the first signaling and the second signaling aretransported via the SV in a transparent mode, wherein enabling thetransport of the second signaling between the plurality of UEs and theCore Network after the second time comprises at least one of:determining a timing for each radio cell in the first plurality of radiocells, wherein the timing is applicable after the second time, andproviding the timing of a serving radio cell in the first plurality ofradio cells to each UE in the first plurality of UEs before the secondtime; determining a timing advance for each UE in the first plurality ofUEs, wherein the timing advance is applicable after the second time, andproviding the timing advance to each UE in the first plurality of UEsbefore the second time; or a combination thereof.
 4. The method of claim3, wherein determining the timing for each radio cell in the firstplurality of radio cells is based on (i) a known orbital position of theSV, and (ii) known or measured propagation and transmission delays for:signaling links between the sNB and the first earth station, signalinglinks between the first earth station and the SV; signaling linksbetween the sNB and the second earth station; signaling links betweenthe second earth station and the SV; and signaling links between the SVand the first plurality of UEs.
 5. The method of claim 1, wherein thefirst network node and the second network node comprise a same satelliteNode B (sNB), wherein the sNB is included within the SV, and wherein thefirst signaling and the second signaling are transported via the SV in aregenerative mode.
 6. The method of claim 5, wherein the first earthstation and the second earth station act as Level 1 relays, whereinenabling the transport of the second signaling between the plurality ofUEs and the Core Network after the second time comprises: transferring,at the second time, a plurality of data links from the first earthstation to the second earth station, wherein each data link in theplurality of data links comprises a Level 2 connection between the sNBand the core network, and wherein signaling for each data link in theplurality of data links is transported through the first earth stationat a Level 1 prior to the second time and is transported through thesecond earth station at a Level 1 after the second time.
 7. The methodof claim 5, wherein the first earth station and the second earth stationact as Level 2 relays, wherein enabling the transport of the secondsignaling between the plurality of UEs and the Core Network after thesecond time comprises: releasing, immediately prior to the second time,a first plurality of data links between the sNB and the core network,wherein the first plurality of data links transports the firstsignaling, and wherein each data link in the first plurality of datalinks comprises a Level 2 connection between the sNB and the first earthstation and a concatenated Level 2 connection between the first earthstation and the core network; transferring, at the second time and fromthe first earth station to the second earth station, a Level 1 transportof signaling between the sNB and the core network; and establishing,immediately after the second time, a second plurality of data linksbetween the sNB and the core network, wherein the second plurality ofdata links transports the second signaling, wherein each data link inthe second plurality of data links comprises a Level 2 connectionbetween the sNB and the second earth station and a concatenated Level 2connection between the second earth station and the core network, andwherein each data link in the second plurality of data links correspondsto one data link in the first plurality of data links.
 8. The method ofclaim 1, wherein the SV is used in a regenerative mode with a splitarchitecture, wherein the SV includes a satellite NodeB (sNB)Distributed Unit (sNB-DU), wherein the sNB-DU communicates with a firstsNB Central Unit (sNB-CU) to transport the first signaling and with asecond sNB-CU to transport the second signaling, wherein the firstsignaling is transported between the sNB-DU and the core network via thefirst sNB-CU, and wherein the second signaling is transported betweenthe sNB-DU and the core network via the second sNB-CU.
 9. The method ofclaim 8, wherein the first sNB-CU comprises the second sNB-CU, the firstnetwork node comprises the second network node, and wherein the firstnetwork node comprises the sNB-DU or the first sNB-CU.
 10. The method ofclaim 9, wherein the first earth station and the second earth stationact as Level 1 relays, wherein enabling the transport of the secondsignaling between the plurality of UEs and the Core Network after thesecond time comprises: transferring, at the second time, a plurality ofdata links from the first earth station to the second earth station,wherein each data link in the plurality of data links comprises a Level2 connection between the first network node and the other of the sNB-DUand the first sNB-CU, wherein each data link in the plurality of datalinks is transported through the first earth station at a Level 1 priorto the second time and is transported through the second earth stationat a Level 1 after the second time.
 11. The method of claim 9, whereinthe first earth station and the second earth station act as a Level 2relays, wherein enabling the transport of the second signaling betweenthe first plurality of UEs and the Core Network after the second timecomprises: releasing, immediately prior to the second time, a firstplurality of data links between the first network node and the other ofthe sNB-DU and the first sNB-CU, wherein the first plurality of datalinks transports the first signaling, and wherein each data link in thefirst plurality of data links comprises a Level 2 connection between thefirst network node and the first earth station and a concatenated Level2 connection between the first earth station and the other of the sNB-DUand the first sNB-CU; transferring, at the second time and from thefirst earth station to the second earth station, a Level 1 transport ofsignaling between the first network node and the other of the sNB-DU andthe first sNB-CU; and establishing, immediately after the second time, asecond plurality of data links between the first network node and theother of the sNB-DU and the first sNB-CU, wherein the second pluralityof data links transports the second signaling, wherein each data link inthe second plurality of data links comprises a Level 2 connectionbetween the first network node and the second earth station and aconcatenated Level 2 connection between the second earth station and theother of the sNB-DU and the first sNB-CU, and wherein each data link inthe second plurality of data links corresponds to one data link in thefirst plurality of data links.
 12. The method of claim 8, wherein thefirst sNB-CU is different than the second sNB-CU, and furthercomprising: enabling the transport of the second signaling between thefirst plurality of UEs and the Core Network after the second time viathe SV by performing a modified handover procedure for each UE in thefirst plurality of UEs, wherein either (i) the first network nodecomprises the first sNB-CU and the second network node comprises thesecond sNB-CU, or (ii) the first network node and the second networknode each comprise the sNB-DU.
 13. The method of claim 12, whereinperforming the modified handover procedure for each UE in the firstplurality of UEs comprises at least one of: releasing first non-UEassociated links and connections between the sNB-DU and the first sNB-CUimmediately before the second time, wherein signaling for the firstnon-UE associated links and connections is transported between thesNB-DU and the first sNB-CU via the first earth station at a Level 1 ora Level 2; establishing second non-UE associated links and connectionsbetween the sNB-DU and the second sNB-CU immediately after the secondtime, wherein signaling for the second non-UE associated links andconnections is transported between the sNB-DU and the second sNB-CU viathe second earth station at a Level 1 or a Level 2; releasing first UEassociated connections and tunnels between the sNB-DU, the first sNB-CUand the core network immediately before the second time, whereinsignaling for the first UE associated connections and tunnels istransported between the sNB-DU and the first sNB-CU using the firstnon-UE associated links and connections; establishing second UEassociated connections and tunnels between the sNB-DU, the second sNB-CUand the core network immediately after the second time, whereinsignaling for the second UE associated connections and tunnels istransported between the sNB-DU and the second sNB-CU via the secondearth station using the second non-UE associated links and connections;or a combination thereof.
 14. The method of claim 1, further comprising:transporting third signaling between a second plurality of UEs and theCore Network at the first time, wherein the third signaling istransported via the SV, the first earth station and the first networknode, wherein the third signaling is transported between the SV and thesecond plurality of UEs using a second plurality of radio cells; andhanding over the second plurality of UEs before the second time to athird plurality of radio cells supported by one or more SVs differentfrom the SV, wherein fourth signaling is transported between the secondplurality of UEs and the Core Network after the second time, and whereinthe fourth signaling is transported via the one or more SVs using thethird plurality of radio cells.
 15. A first network node configured fortransferring signaling for a first plurality of radio cells from a firstearth station to a second earth station, wherein the first plurality ofradio cells is supported by a space vehicle (SV), the first network nodecomprising: an external interface configured to communicate with networknodes; at least one memory; at least one processor coupled to theexternal interface and the at least one memory, wherein the at least oneprocessor is configured to: transport, via the external interface, firstsignaling between a first plurality of User Equipments (UEs) and a CoreNetwork at a first time, wherein the first signaling is transported viathe SV, the first earth station and the first network node, and whereinthe first signaling is transported between the SV and the firstplurality of UEs using the first plurality of radio cells; cease totransport the first signaling between the first plurality of UEs and theCore Network at a second time, wherein the second time is subsequent tothe first time; and enable the transport of second signaling between thefirst plurality of UEs and the Core Network after the second time viathe SV, the second earth station and a second network node, wherein thesecond signaling is transported between the SV and the first pluralityof UEs using the first plurality of radio cells.
 16. The first networknode of claim 15, wherein the first signaling and the second signalingcomprise user plane signaling and control plane signaling, wherein theuser plane signaling includes signaling for data and voice connectionsbetween each of the plurality of UEs and external entities, and whereinthe control plane signaling includes signaling for connections andassociations between each of the plurality of UEs and entities in theCore Network.
 17. The first network node of claim 15, wherein the firstnetwork node and the second network node comprise a same satellite NodeB(sNB), wherein the first signaling and the second signaling aretransported via the SV in a transparent mode, wherein the at least oneprocessor is configured to enable the transport of the second signalingbetween the plurality of UEs and the Core Network after the second timeby being configured to at least one of: determine a timing for eachradio cell in the first plurality of radio cells, wherein the timing isapplicable after the second time, and provide the timing of a servingradio cell in the first plurality of radio cells to each UE in the firstplurality of UEs before the second time; determine a timing advance foreach UE in the first plurality of UEs, wherein the timing advance isapplicable after the second time, and provide the timing advance to eachUE in the first plurality of UEs before the second time; or acombination thereof.
 18. The first network node of claim 17, wherein theat least one processor is configured to determine the timing for eachradio cell in the first plurality of radio cells based on (i) a knownorbital position of the SV, and (ii) known or measured propagation andtransmission delays for: signaling links between the sNB and the firstearth station, signaling links between the first earth station and theSV; signaling links between the sNB and the second earth station;signaling links between the second earth station and the SV; andsignaling links between the SV and the first plurality of UEs.
 19. Thefirst network node of claim 15, wherein the first network node and thesecond network node comprise a same satellite Node B (sNB), wherein thesNB is included within the SV, and wherein the first signaling and thesecond signaling are transported via the SV in a regenerative mode. 20.The first network node of claim 19, wherein the first earth station andthe second earth station act as Level 1 relays, wherein the at least oneprocessor is configured to enable the transport of the second signalingbetween the plurality of UEs and the Core Network after the second timeby being configured to: transfer, at the second time, a plurality ofdata links from the first earth station to the second earth station,wherein each data link in the plurality of data links comprises a Level2 connection between the sNB and the core network, and wherein signalingfor each data link in the plurality of data links is transported throughthe first earth station at a Level 1 prior to the second time and istransported through the second earth station at a Level 1 after thesecond time.
 21. The first network node of claim 19, wherein the firstearth station and the second earth station act as Level 2 relays,wherein the at least one processor is configured to enable the transportof the second signaling between the plurality of UEs and the CoreNetwork after the second time by being configured to: release,immediately prior to the second time, a first plurality of data linksbetween the sNB and the core network, wherein the first plurality ofdata links transports the first signaling, and wherein each data link inthe first plurality of data links comprises a Level 2 connection betweenthe sNB and the first earth station and a concatenated Level 2connection between the first earth station and the core network;transfer, at the second time and from the first earth station to thesecond earth station, a Level 1 transport of signaling between the sNBand the core network; and establish, immediately after the second time,a second plurality of data links between the sNB and the core network,wherein the second plurality of data links transports the secondsignaling, wherein each data link in the second plurality of data linkscomprises a Level 2 connection between the sNB and the second earthstation and a concatenated Level 2 connection between the second earthstation and the core network, and wherein each data link in the secondplurality of data links corresponds to one data link in the firstplurality of data links.
 22. The first network node of claim 15, whereinthe SV is used in a regenerative mode with a split architecture, whereinthe SV includes a satellite NodeB (sNB) Distributed Unit (sNB-DU),wherein the sNB-DU communicates with a first sNB Central Unit (sNB-CU)to transport the first signaling and with a second sNB-CU to transportthe second signaling, wherein the first signaling is transported betweenthe sNB-DU and the core network via the first sNB-CU, and wherein thesecond signaling is transported between the sNB-DU and the core networkvia the second sNB-CU.
 23. The first network node of claim 22, whereinthe first sNB-CU comprises the second sNB-CU, the first network nodecomprises the second network node, and wherein the first network nodecomprises the sNB-DU or the first sNB-CU.
 24. The first network node ofclaim 23, wherein the first earth station and the second earth stationact as Level 1 relays, wherein the at least one processor is configuredto enable the transport of the second signaling between the plurality ofUEs and the Core Network after the second time by being configured to:transfer, at the second time, a plurality of data links from the firstearth station to the second earth station, wherein each data link in theplurality of data links comprises a Level 2 connection between the firstnetwork node and the other of the sNB-DU and the first sNB-CU, whereineach data link in the plurality of data links is transported through thefirst earth station at a Level 1 prior to the second time and istransported through the second earth station at a Level 1 after thesecond time.
 25. The first network node of claim 23, wherein the firstearth station and the second earth station act as a Level 2 relays,wherein the at least one processor is configured to enable the transportof the second signaling between the first plurality of UEs and the CoreNetwork after the second time by being configured to: release,immediately prior to the second time, a first plurality of data linksbetween the first network node and the other of the sNB-DU and the firstsNB-CU, wherein the first plurality of data links transports the firstsignaling, and wherein each data link in the first plurality of datalinks comprises a Level 2 connection between the first network node andthe first earth station and a concatenated Level 2 connection betweenthe first earth station and the other of the sNB-DU and the firstsNB-CU; transfer, at the second time and from the first earth station tothe second earth station, a Level 1 transport of signaling between thefirst network node and the other of the sNB-DU and the first sNB-CU; andestablish, immediately after the second time, a second plurality of datalinks between the first network node and the other of the sNB-DU and thefirst sNB-CU, wherein the second plurality of data links transports thesecond signaling, wherein each data link in the second plurality of datalinks comprises a Level 2 connection between the first network node andthe second earth station and a concatenated Level 2 connection betweenthe second earth station and the other of the sNB-DU and the firstsNB-CU, and wherein each data link in the second plurality of data linkscorresponds to one data link in the first plurality of data links. 26.The first network node of claim 22, wherein the first sNB-CU isdifferent than the second sNB-CU, and the at least one processor isfurther configured to: enable the transport of the second signalingbetween the first plurality of UEs and the Core Network after the secondtime via the SV by performing a modified handover procedure for each UEin the first plurality of UEs, wherein either (i) the first network nodecomprises the first sNB-CU and the second network node comprises thesecond sNB-CU, or (ii) the first network node and the second networknode each comprise the sNB-DU.
 27. The first network node of claim 26,wherein the at least one processor is configured to perform the modifiedhandover procedure for each UE in the first plurality of UEs by beingconfigured to at least one of: release first non-UE associated links andconnections between the sNB-DU and the first sNB-CU immediately beforethe second time, wherein signaling for the first non-UE associated linksand connections is transported between the sNB-DU and the first sNB-CUvia the first earth station at a Level 1 or a Level 2; establish secondnon-UE associated links and connections between the sNB-DU and thesecond sNB-CU immediately after the second time, wherein signaling forthe second non-UE associated links and connections is transportedbetween the sNB-DU and the second sNB-CU via the second earth station ata Level 1 or a Level 2; release first UE associated connections andtunnels between the sNB-DU, the first sNB-CU and the core networkimmediately before the second time, wherein signaling for the first UEassociated connections and tunnels is transported between the sNB-DU andthe first sNB-CU using the first non-UE associated links andconnections; establish second UE associated connections and tunnelsbetween the sNB-DU, the second sNB-CU and the core network immediatelyafter the second time, wherein signaling for the second UE associatedconnections and tunnels is transported between the sNB-DU and the secondsNB-CU via the second earth station using the second non-UE associatedlinks and connections; or a combination thereof.
 28. The first networknode of claim 15, the at least one processor is further configured to:transport third signaling between a second plurality of UEs and the CoreNetwork at the first time, wherein the third signaling is transportedvia the SV, the first earth station and the first network node, whereinthe third signaling is transported between the SV and the secondplurality of UEs using a second plurality of radio cells; and hand overthe second plurality of UEs before the second time to a third pluralityof radio cells supported by one or more SVs different from the SV,wherein fourth signaling is transported between the second plurality ofUEs and the Core Network after the second time, and wherein the fourthsignaling is transported via the one or more SVs using the thirdplurality of radio cells.
 29. A first network node configured fortransferring signaling for a first plurality of radio cells from a firstearth station to a second earth station, wherein the first plurality ofradio cells is supported by a space vehicle (SV), the first network nodecomprising: means for transporting first signaling between a firstplurality of User Equipments (UEs) and a Core Network at a first time,and wherein the first signaling is transported via the SV, the firstearth station and the first network node, wherein the first signaling istransported between the SV and the first plurality of UEs using thefirst plurality of radio cells; means for ceasing to transport the firstsignaling between the first plurality of UEs and the Core Network at asecond time, wherein the second time is subsequent to the first time;and means for enabling the transport of second signaling between thefirst plurality of UEs and the Core Network after the second time viathe SV, the second earth station and a second network node, wherein thesecond signaling is transported between the SV and the first pluralityof UEs using the first plurality of radio cells.
 30. A non-transitorystorage medium including program code stored thereon, the program codeis operable to configure at least one processor in a first network nodefor transferring signaling for a first plurality of radio cells from afirst earth station to a second earth station, wherein the firstplurality of radio cells is supported by a space vehicle (SV),comprising: program code to transport first signaling between a firstplurality of User Equipments (UEs) and a Core Network at a first time,and wherein the first signaling is transported via the SV, the firstearth station and the first network node, wherein the first signaling istransported between the SV and the first plurality of UEs using thefirst plurality of radio cells; program code to cease to transport thefirst signaling between the first plurality of UEs and the Core Networkat a second time, wherein the second time is subsequent to the firsttime; and program code to enabling the transport of second signalingbetween the first plurality of UEs and the Core Network after the secondtime via the SV, the second earth station and a second network node,wherein the second signaling is transported between the SV and the firstplurality of UEs using the first plurality of radio cells.